Because you had a period and a sonogram dated you at 6.5 weeks at the time, it is the friend's baby. He doesn't have to ejaculate in order to get you pregnant as pre-ejaculate contains sperm.
Early sonogram measurements are the most accurate and I would trust that it is correct. There is a 2 week gap between Oct. 20th and Nov. 2nd so if you did conceive in October you would've been much further along.
it could be either guys. even if the friend didn't ejaculate there is still pre ejaculate that is secreted through the penis during sex. it DOES contain sperm. it takes one sperm to get you pregnant. like smj said you're going to need a paternity test. good luck to you.
It's possible either way. Depending on when you ovulated. It takes 6-12 days for an egg to implant and actually give off the HCg hormone. You're probably going to need a dna test, but if I had to guess, I'd say it was your boyfriend, but again it could go either way.