Last wknd, I stayed over a friends place (guy). Whn Sunday came around we werent speaking to eachother...?

Last wknd I stayed over at a friend's place (guy). I wasnt rude to him while in his home. We went to lunch on Saturday and he went to work. Met up with him later in the night. Had a feeling things btwn us went sour, but didnt want to believe it, until Sunday happened. Whn Sunday morning came around, we werent speaking to eachother. He dropped me off and havent heard from him since. Wht should I do? or should let the issue alone