Am I Going Crazy..............?

So, i am getting a little scared. I live alone, and things seem to be disppearing, and reappearing in sports that i did not put them. For instance, i have been frantically looking for my 50 doller bill that i was going to give to a friend that i borrowed money from. He came over my house, but before he got there, i couldn't find the money. I told him that i didn't know what happened to it, and that I honestly am not trying to cheat him. So, after a week of looking i got up on morning and found a 50 doller bill on my kitchen counter, which i use everyday. this obviously wasn't there when i went to sleep last night, and now im getting a little paranoid...I told my friend about it, and he thinks im playing games with him, and am trying to cheat paying him the money...