Boyfriend, brother, and a baby...

I've been dating this guy for two years now and we've had s** quite a few
times.

My mom never liked him and I dating and, this morning, she said that she
had something she wanted to talk to me about. Well, it turns out that he's
actually my older brother that she gave up for adoption. The family used to
live in Utah but they moved back here and that's how we met. I love him so
much and we refuse to break up.

I was planning on telling my mom that I'm pregnant with his baby... Now I
don't know what to do! Help!