Is there such thing as a chess slump?

Got frustrated tonight with my chess playing.  I missed a lot of moves that, in retrospect, were easy moves.  Dropped quite a few games in a row, and that's never happened before.  Anybody else ever experience that? Thanks

Slumps occur to everyone. (Even Magnus has lost recently.) Don't worry too much. 

You played at least 11 hours of chess yesterday. (I see eleven 30 0 games yesterday in your archive.)

You need to give your eyeballs a rest occasionally.

carlsen loses al the time. poeple think is unbeateble or something. his winning change against a 2760 rated plater is  64%

and u also have slump's somethimes i lose 200 points and it takes me weeks to get them back

Thank you for the kind words. Makes me feel better.  Now I gotta make up some ground.