Angry spouse

I’m very confused as to what is happening to my partner he’s always been such a good hearted man, he said he had stopped smoking and drinking recently which I noticed he did, but his personality has gone off the deep end..he has been working a lot to keep up with support in our home, I have been here minding my own business not even talking to anybody at all and now my partner thinks that I have cheated on him because he found a toothbrush that I can’t even remember where it came from and a swim suit top that he swears is a (sexy bra)I wore one time that has been sitting in my closet for years and by the way he saw me wearing it two years ago. He went absolutely crazy mad yesterday saying how I have ruined our bedroom and that their isn’t any way that I haven’t been cheating on him threw trash everywhere and then he left for hours to go to the gym and was posting weird Instagram stories,came home and wouldn’t talk to me . I don’t have my phone blowing up ,I’m not acting any differently, I show no signs of cheating other than he keeps finding things in our house that he thinks belongs to someone else... I haven’t slept in three days I’m sick to my stomach and I have a one year old to take care of...am I missing something?!