I don't know if Im still a virgin or not

Help!!! my name is chelsey and i went to a party yesterday. i was drinking tequila and i remember that we were dancing. all of the sudden i wake up in robert's house (he's the guy that i started dating two days ago). i woke up and he wasnt there no more, he had gone to work. my clothes where all in place, but the problem is that i was wearing a skirt. later on i asked him if something happened and he said no. i dont know if i should believe him because some of my friends told me that he took me to a room. he said its becuase i said i wanted to go to sleep. my question is Is there a way to know if im still a virgin or not??? What do you feel after losing your virginity??? how can i find out??? . thanks for any help that you could give me.