I'm not so sure if I'm still a virgin or not or even if I have a STD?

A couple of weeks ago on a Friday night, I ended up getting drunk and I think I might have had with a guy that night. I'm not even so sure what I drank but I had three drinks and someone was saying that there might have been some drugs in the drink because I totally blacked out for like 8 hours and I don't even remember returning back to my dorm. I remember throwing up nachos and two seniors from college took me to party afterwards where there was drinking and I had three drinks. Although I don't remember what happened after I drank them but I think I might have had . Apparently, I wrote "tzaking " on my facebook status and when I woke up to screaming sorority girls inside my residence hall my was hurting a little. I don't know who it was with or anything and I'm not even so sure if they were clean because if I really did have it I don't think I wore protection. I don't really want to tell my family or too many adults but my friend thinks this is a real serious problem. I really don't think it's serious because for some strange reason I don't think I actually did it and all of my roommates said that I was in the room for most of the night and I did not have in the room at all. I don't really know what to believe because I blacked out and I don't really want to get anyone in trouble if something really did happen. What should I do?