I'm sh*gging my boss.....?

Ok, here we go. I am having an affair with my boss......and I've just found out that I am up the duff. I don't know who the father is because my boss is also my boyfriends DAD! I'm in deep doo doo and don't know what to do. On the bonus side though, at least I won't have to worry about the surname on the birth certificate! Any advice will be greatly appreciated.