Hi, I wasn't sure where else to post this and I'm trying to find an answer...

My friend and I had unprotected sex twice in a month, and then she had her period, though her period was late. After her period she had sex at a party; now she's missed her period entirely and a home pregnancy test came back positive rather quickly. She's insisting that there's no way it could be mine because she had her period but I've read that it's common for a woman to have her period once or twice after conception before missing it.

So is it possible that the kid could be mine?