Is it possible to get worse at understanding chess?

Recently, I'm in a slump and I've been making more and more mistakes especially with regards to tactical calculations and positional play.

I'm low rated and play G30 for improvement, but I generally know that material can be compensated with good piece activity, space, initiative, etc.. However, recently, I've noticed that I've lost it. I can't formulate a plan, I keep giving my opponents the initiative, I'm not calculating tactics well, and I cling too much to material which I inevitably lose.

That's why I started training using Silman's Amateur's Mind which I find really instructive and well; but again, in actual play, I find myself more and more like a deer in the headlights.

Can you guys give me an advice? I really want to reach that 1500 rating, my lifelong goal is 2000 even if it's just here in this site

I have a suggestion.

1- see games of good players on you tube like Mikhail Tal, Bob fisher, Carlson, Vishwanathan Anand, Nakamura and more rated players.

2- try to understand their attacking style, and adopt it.

3- focus on making plan,

4 - but don't stick with one plan during game, 

5- continuously try to think, find mistakes of opponent and take advantages 

Man, im in the same boat, went on a nice win streak then just fell on my face.

Yes

I’m much lower than you, but it seems the more I learn... the more I learn that I have more to learn. Much, much more. 

Good advice here, yet it sounds to me as though you're too anxious about winning & ratings. I would suggest just rolling with it, that is; Regain a sense of adventure & rediscover the enjoyment of the game, be willing to take risks/sacrifices/etc., without worrying so much if it becomes a loss. I will also share that when I have slid into "slumps", it is usually when I've been playing for too long and/or too often. That sometimes brings with it a loss of concentration, & becoming more easily distracted by something else happening offline, etc. Just remember, if it's no longer much fun, then it's probably time for a break?! Peace...+

no, its not

These are good suggestions, sir. I also appreciate our games last time, I've analyzed them and somewhere in those games, I went blank. Have you noticed anything else which I can improve on?

Thank you, sir. I haven't been doing puzzles much lately, I'll try that

Right? You think you figure out something, and then you get crushed playing the same way next time. But chess is really fun

This is good advice, and it makes sense. Maybe I am too worried about winning and my rating, so much that I'm not taking the risks. I'll try to play more gambits and see how I'll do then

It remains fun and challenging. There are days i have to put it up and wonder “why?” As long as i continue to enjoy the game and it challenges my brain I’ll keep at it. If and when that day comes I’ll try something easier, like time travel or alchemy. 

Happens to all of us, I suppose

Evidently it is possible, I just played a game where I hung two bishops in a row after thinking for a while.

Defeats are not so bad for me usually, I’m a good sport when I’m outplayed, but I simply started sobbing in self hatred after that display of utter stupidity.

I rarely if ever hang pieces in OTB games, but in online games I suddenly become the stupidest person alive.

But the mistakes you describe seem mainly to be positional, as opposed to blundering whole pieces like I do. 

If I got to a rating of 1600 despite this, just about anyone can.

Hang in there!

Of course, this is advice about chess coming from an incompetent patzer like myself, so take it with a grain of salt. 

Yeah that's one of the most annoying parts.

What advice can you give to get to 1600?

When you study, you learn about new things. This means during a game, you'll be more confused, because you won't know when and how to incorporate those new ideas.

That's normal. It sorts itself out over time. Just keep playing.

Thank you for your advice. You must be the highest rated llama in history lol

As for how I personally got to 1600, I just did about 50 tactics puzzles a day on lichess, and I watched videos about opening theory, tactics and endgames from Gothamchess, St. Louis chess club, Hanging Pawns, and the like.

A lot of good advice in here and I can relate to the OP.  I only returned to playing chess a few months ago and at first had that "sense of adventure" and loved learning.  I play Daily games and then analyze afterward to see where my strengths and weaknesses were.  I also do puzzles every day and was slowly climbing until I seemed to fall apart last night.  The degree to which I let go worrying about losing or not getting a puzzle solution is related to how much I enjoy playing.  Sometimes we forget that it's a lifelong struggle to learn and get better and most of us are not going to make the "best move" every time.  I strive to get better without beating myself up when I make a mistake or struggle in a game.  I occasionally need to remind myself that I do this for the love and adventure of the game.  Good luck!