If what you just said happened that way, it was VERY rude, selfish, immature and stupid of your boyfriend to do.
It is never your fault that it hurts, nor will it ever be.
You aren't a machine that has a green and red button, and when someone pushes the green one you re ready to go.
You said that your boyfriend said he was sorry and that he didn't "mean" to say such stuff.
You should tell him, never ever to say that again to you.
When it comes to your friends and his friends, first of all it's not their buissnes to take side, nor should you try to make them take side, you shouldn't even care about who made the "fault" or who thinks what, it is what you feel that matters.
I don't know how you said stop to your boyfriend, and if you did explain anything further, but try to reason with him, and communicate with him in a better way, if he still is the "same", then I really doubt that it is a good idea to have sex with him at all. (Hope you understand what I mean here, It's a big diffrence saying stop and trowing him away, or saying that it hurts and that you don't want to do this)
My conclusion is, that your boyfriend was very inconsiderate, and immature.However there is no point in being ms right, or mr wrong or whatever, so try to focus on making things better
If your boyfriend can't accept you as who you are and how you feel, then really, sex won't be great because it takes a lot of patience, commitment, and ->communication<-