Please, help me analyzing this.

Maybe black is ok after immediate 20...Qf8 21QxQ RxQ 22f4 white can't get Ne6.

 Bye John S

After your flurry of exchanges, you had a green light to proceed with your attack on the white king.  The white queen cannot win the game on her own, so you could have felt comfortable leaving her alone.  20...Rf7 slightly better is 20...a4.  Advantageous moves to look at after 19...Rxf5 are (bear in mind that these are not in any particular move order, but rather, are moves to consider from this position): Rh5; Nc4; a4; e6.  These are all separate, isolated moves for black to consider after the 19th move.  20. Ne2 doesn't seem to impress me mainly because of black's queenside attack.  To me, it seems like the one defender for white on that side had been removed on white's 20th move.

39...Rc8.  I tend to favor 39...Ra8, claiming the file.

Now, I read your comment on move 45.  You defeated yourself before white defeated you.  you had a decent enough of a defense that would make the game more difficult for white to win.  Alternatively, you could have played either  Rd7 or e4+.  So, with you going kamikaze, led to your "suicide", so to speak.

The way the opening is played looks ok to me. But, I think the Pirc is a deceptively "safe" looking opening... no, you don't get quick killed in a pirc like you do in a badly played King's Gambit or Sicillian... but it calls for expert positional judgment, and lacking that, you end up cramped, defensive, and passive, which is exactly what happens to you here. 

1. Your game falls apart around one seemingly innocuous move... exactly the kind  of passive planless move you want to avoid. 20.Rf7? All this does is give away precious tempo. Your opponent takes advantage immediately.

At move 20... you want to activate your pieces, you've got a rook on the a-file with nothing to do. The half open f-file looks like a great spot for doubled rooks.   Instead you make a meaningless defensive move. 20.Rf7? what does this accomplish? Why did you need to retreat? Your opponent responds, and it isn't by defending...he uses your passivity to get his N all up in your business.

22.Qxf8+ and you recapture Kxf8... it looks awful, Rxf8 looks much better at first glance, but truth is, the mistake was on move 20.  Now, it's too late. 22...Rxf8 doesn't answer 23.Ne6 any better than than Kxf8 did. The rook gets chased off the f-file.  If you could have gotten those rooks doubled up before the N penetrates, it's would be different story. 

Please notice that on move 24, you move your rook back to Rf5...20.Rf7 cost you the file and wasted two tempos (one moving away, and one moving back!) f5 was a fine square for the rook. 

Some blunders hang a piece...other blunders, like Rf7 look completely harmless...hey all it did was a bring a piece back to a "safer" spot? How bad could that be? -- Answer: bad. 

It looks to me like when you have a distinct goal, you do okay finding moves... You decide his N needs chasing, and you do a good job of chasing his N out of your position.  But as soon as you have to accomplish something for yourself  -- well, you don't seem able to form a clear offensive goal of your own. Your motto appears to be, when in doubt, retreat and defend -- That is a 100% losing philosophy. 

 35. Nf8?!  What was the point of this? Defending a pawn that is already defended  and isn't being attacked? 

39. Rc8? Your concentration appears to be waning, this is just silly stuff. The a-file is open and your rook should be hungry to get there, your b pawn is hanging and must be defended...instead you put your rook on the c file.  Your opponent cuts you some slack and finds a way to not take the free material right away. And now, again with clear defensive goals you weasel and dodge and manuver your way into a postion, which against all odds, gives you fighting chance... and then you play: Nd4??

Kamikaze? what? If you can't find better than this, for God's sake resign. This is wood pushing. You were doing good! You were defending, counter-thrusting with the pawns, making him at least earn his gains... and then you just thow it away. Don't do that. Resign or make real moves. There are more blunders in the finish, but after Nd4 there is no point in continuing to analyze, or play.

Just looking a bit more at 45...Nxe5, 45...Rc7 is a simple option then 46Ra7ch Ke8. 47 Nxp Rc3ch 48Kd2 Nf3ch 48Kd1 Nxp maybe black can get away with something like this.

Bye John S

KID setups (like the pirc) are infamous for not letting you know where you messed up, so don't feel bad.

7. d5?! is not the best idea.  Between the extra bishop pressure, the twice moved pawn, the less useful knight its not clear why you would play d5.  It doesn't break whites center, it relieves pressure on it (the moved knight)!  

8. Ne8 was not your only option, there is a line I've memorized that allows you to keep material after Nd5, and Nce2 immediately adds central pressure (at the cost of knight flexability. 

15. Rf7! was missed (you played b4), but Nh4?! saved you (The threat of Nh4 was stronger then the execution)

16. f5?? could have killed you via Nf3, note that if the knight protects, the pawn structure falls. You are wrong about it being forced.  fxe6 (allowing Rf6) would have saved you for example, note that you don't have to retake after a piece takes f6.  The line seems risky, but it works, and its better then death by Nf3.

17. Nxg5? worse then Bxg5, which either forced white to trade off all attackers, or retreat the queen.  White decided to trade off his attackers anyways for whatever reason, and gave you the advantage.

20. Rf7? was a waste of time that cost you the advantage, worrying about black controlling the file is wrong.  First, you have lots of control on the A file, and even more to the point Qf8 (note Raxf8) allows YOU to control the file for no compensation he wouldn't otherwise have.  Furthermore, he would have to retreat or trafe off his queen, so not a bad deal.

Ke7?  neglected the g file for no gain.

h5? made the g pawn even more vulnerable. It would be a mistake for white to advance, so that shouldn't have been a concern.  You also spent a tempo on creating a backwards pawn for yourself.

45. Nd4?? made you lose.  You still had winning chances, and shouldn't have resigned (or in your case, ugh, "kamikazied")

50. Rh2+??, which was mate in 7 if white advanced his king towards your rook.  53. d3?? ignored mate in 2.

Adding so many defenders later in the game to the queenside was passive and unnessecary in many cases.

What you did wrong this game was get intimidated by your opponent.  Throughout the game, you made mistakes purely because you thought your opponent had stronger moves then he actually did (the H pawn push, Rf7?, f5??, and Nd4?? all come to mind).  Don't ignore moves just because they seem risky!