What went wrong here?

This is a game I lost a few hours ago and I was wondering what I should've done to avoid that.Any suggestions are apreciated ^-^

can't see for sure, maybe something like ...

Heres a good Bxf7 combination:-

Bxf7 was of course horrible. Keeping your opponent from castling isn't worth a bishop for a pawn unless you have tactics that call for it or a specific attack. Nor is going out of your way and having a bad position worth it. All you do is slow him down by a tempo or two and that is hardly worth losing a bishop.

You said "I want to keep him from castling no matter the cost". That thinking will do you no good.

Ba3 was good. If your goal was to stop castling, Qd6 or probably better Bd6 would have been an alternative that actually wasnt bad as he has to deal with losing his e pawn. It also cramps his position majorly by stopping d6 or d5.

You over commit in a position, need to be more patient and defensive minded.  If you can't find something to do, it will not help to sacrifice a piece if there is no follow up.

That said, if you do sac anyway that's fine, but you're required that your remaining pieces be able to overwhelm  the opponent in some way.  After Bxf7 you have maybe 2 pieces you can bring into an attack... the queen and the bishop.  The f3 knight can't really get close enough.  Now you count black's defenders... and unless you have a forcing variation or some other special case if his defenders aren't two less than your attackers then your attack is likely to fail.  Black has 3 defenders and can bring at least 1 more using only 2 moves, so you're 3 attacking pieces short of an attack.

As you saw moves like Nh4 and Bd6 were too slow even if the ideas were good behind them (opening lines, bringing attackers closer).  But it takes more than a phrase out of a book to make a move good.  When you can attach such a phrase (I'm centralizing, I'm taking the open file, I'm castling to safety) but the move isn't good in that specific position, it's called an artificial move.  The kinds of things you were describing your pieces doing were good, but in that position they were artificial moves.

Anyway remember to count if your force in an area is superior (attackers vs defenders).  Not a golden rule, but will give you a quick estimate if a sacrificial attack is called for or not.  If not, but you still want to sacrifice, then point some more pieces toward that area and look for sacs again later :)

wafflemaster and mtguy8787 ,thanks for your observations.I admit that Bxf7 was a bad move.However,under what circumstances is an artificial sacrifice effective and how should the material balance look after it?

get houdini. plug in the values. if you can't do that you are beyond hope.

Anyway I think (despite being ignored) that they where trying to tell you to play safer moves in certain positions.

The point is the pieces have relative values.  They're relative because they change based on how useful (active/mobile) the piece is (or can become).  When you sacrifice material based on the relative values, you're usually looking for compensation in some form of activity.  It may mean an attack, it could mean a positional bind, but the point is you will have some pieces, at least in one area (kingside / queenside) that are working harder than your opponent's so to speak.  Or maybe you simply outnumber them in that area.  This is what the board should look like after a sacrifice.  It's not a material count, we've all seen Morphy games (or similar famous combinations) where the attacker sacrifices nearly his whole army, but the point is the remaining pieces deliver mate so it was worth it.  If you look in such positions you'll often notice half the opponents army is stuck, useless, on the other side of the board.  This is another thing to look for.

So in the case of wanting to attack, I was saying you should see if your attackers outnumber the defenders.  This is just a general idea to look for, many great games involve brilliant attacks where this wasn't strictly necessary.  But if you don't see a brilliant forced win, it's something to be cautious of.

 Yeah,I have this tendency of sacrificing material in an irational way.I also agree 10.Qd6 is a very good move

Hi, it doesn't seem like you are very familiar with sicilian defense. The pawn secrifice in the beginning isn't in your favor. Also the isolated 3 pawns in the beginning is also favor in black. With damaged pawn structures, I would not sacrifice the bishop. Sicilian defense is very strong if played correctly. It is kind of hard for a person who isn't familiar with sicilian to attack it. Good luck in your next game.

Its a perfectly fine idea at lower level play, with the general idea not being much different from the danish gambit. Just because an idea is "theoretically not as good" doesnt mean that it necessarily makes a difference for lower level play, because small theoretical differences arent going to be taken advantage of by non-master players, much less lower class players.

At a level where each player will blunder at least several times per game, in fact, an approach where you get better developement and a strong initiative can be superior, when the same idea would not be sound in a master game.

In addition, knowing that "so-and-so move isn't theoretically sound" does absolutely nothing for a class player to improve their understanding.

Without the pawn on h3, Bxf7+ might have had some play (not sure, though), but with no way to follow up (with either Ng6+ or Ne6+ opening up a way to get your queen into the attack), I think this move was the start of your downfall in this game.

Instead of 7. e5 White should play 7. N-e5 and if 7..., BxQ then 8. Bxf7 ++. Black is forced to retreat his bishop to e6 and then white doubles he pawns. Retreating the bishop to h5 does not work because of QxB and then Bxf7 ++

Qd6 would have worked nicely from about moves 10-13.