Don't worry about a little show of blood - it really is nothing to worry about.
If your bf really has a 9" penis, that's extremely large and far too long to put most of it inside most women. He's probably been banging against your cervix and that bleeds very easily. Most women have only 4" to 5" of vagina, so if you're average-sized, then he shouldn't go in more than half the length of his penis. For most women, a 5" to 6" penis is ideal and even a 3"-4" will work perfectly satisfactorily.