I put the wrong name.

I had an interview on Monday and it went really well. He asked me if I wanted to do homework and send him a pitch email. I did the email and sent it off the next day. I just realized I put the wrong name, his name is Bob and I put Brad. I even sent a second email with it to give him context, as I was referring to two things from two articles. I'm mortified, the interview went well, I can't believe I did this. Should I send and email to apologize for the mistake and follow up? ..or maybe wait til tomorrow morning.