Girlfriend almost broke up with me over rough sex

Been dating girl for a little over 4 months and it's been fun although some minor stresses.  Anyways last Thursday she stayed over we had sex in the morning and then when I'm fucking her from behind I tell her I want to cum on her face and she screams nooooooo, I then just cum inside of her, she leaves shortly after.  Were suppose to hang later that night but she tells me her family dinner was later than thought and she doesnt feel well so she is staying in, I then say hope you feel better babe to which she responds I'm not sure I like being called babe.  Next day I ask her how her day is going and she gives short one word responses and I ask her if hanging tonight was cool and she said no, just being really distant.  She text me Sunday saying she wants to talk and she might want to break up, but we should talk.  I tell her I agree but lets not make quick decisions we need better communication about some things and she says ok. 

We meet up and at first I didnt know why she wanted to break up a week earlier she was glad to see me, I ask her if there is another guy, no I ask if its because it's semi-long distance, no.  She then says she doesnt want to have sex anymore, and I start figuring out its the sex.  I've been reading up on The Sex God Method and some other sources and when I have implemented them they have worked well with my gf except this time.  I then tell her we wont have rough sex anymore, she starts saying we might not be right for eachother and I say we also might be.  We get a little emotional and then I say stuff like you mean so much more to me than sex, we wont have sex again till your ready and she eventually agrees.  She then asks me why I did it?  I say I wanted to try something new.  Now this girl isn't a freak, she was weirded out about giving head when we first started dating but she is attractive and we click well.  After some talking I convince her to come to my apartment, no sex, and just chill and watch a movie which we did, I then only hug and briefly kiss her goodbye.  We are suppose to hang out again this Thursday.  What I learned is that girls like to be dominated in bed but not feel disrespected, she must have felt that.  I'm thinking of bringing up at the beginning of our hang out Thursday that I'm glad to see her and that if I ever do anything that makes her uncomfortable emotionally, physically, or sexually to just let me know because I will stop and never do it again.  Manwhore and other vets, how should I go about this?