What the heck is wrong with my tennis...?

OK so these last 2 days my game has just been OFFFFF. I played in a tournament yesterday and got crushed by people who I normally would easily take care of. I couldn't hit anything as hard as I usually can, they would just go into the net or long. My serve just also wouldn't go in. Then today I come out to play with a friend looking to shake off my horrible day and another horrible day comes. My strokes felt sloppy and it felt as if I just couldn't hit the strings even if I tried. Is this just a string of bad days or might there be something wrong because just 3-4 days ago I was fine...