advice

I'm ashamed to say this but I really don't know what to do.. I had a one night stand with a guy who didn't speak a great deal of English. I found out I'm pregnant i literally no nothing about him apart from the street he lives on. he lived in a shared house so going and knocking on all doors isn't an option (likely case is someone else will answer) I just don't know what else to do I don't remember his name or anything about him just what he looked like really. I really don't want to bring my child into the world and leave some man not knowing he even has a kid that exists or not being able to tell my child who there father is.. please don't judge me as I'm not happy about this but it's happened.. has anybody got any advice or suggestions or even a similar story.. it's really getting me down