I got pregnant and I don't know who the father is.

I went out on drinks with some friends one night. We were about 8 or maybe 10 in a group and we were in this club. So we just went dancing and we were all having fun. A foreign guy approached me and asked me out to dance with him and of course, I did. I mean, who would say no to a gorgeous guy, right? We kept drinking and dancing and the next morning, I just found myself lying in an unfamiliar bed and naked. I tried to look if somebody else was around but nobody was. A month later, I keep feeling dizzy and I keep vomiting. Panicked, I went on for a check-up where the doctor told me I was pregnant. I suddenly remembered waking up in that bed and I knew by then that whoever the guy I spent the night with is the father. However, who is he? I tried asking my friends and they seem to not know of what happened to us because everyone was drunk and wasted as hell. What do you think should I do?