I am lost... How to get back my game....

[CallCallCall]

I can tell from your post, that you have little confidence left in your play. Moving down sounds like the wise thing to do.

Start reading your books again. I found Ace on the River great for the mental aspects of the game. I believe tilt control to be the most important skill in this game. Learn to be honest with yourself when you are on tilt (slight or full on). Then either calming yourself down and start playing good poker or quit for the day.

When you lose a big pot, don't think about the result, think about how you played the hand. If you played it well, then fine. If you are not sure or think you might have made a mistake, post the HH in the forum.