Sex Fear and anxiety ?

I went to have a sex with women with my friends , actually I don't have any interest to go with my friends, I didn't do any thing in her room and came back from her room.from that time onwards I unable to stop my mind negative thinkings like I'm I gay. Before going to that place previously my sex desires are too high. Now I'm fearing and anxiety. If I see any gay Iam too fearing. I want to enjoy family life.Plz help me how can I over come my problem.