What do I do if I accidentally called out my ex's name during ?

Okay, technically it wasn't , it was during . I broke up with my 4 years ex because he abused me for about a month now. I've been seeing this other guy who I knew since grade 11. I know I am moving too fast but it just got me when we kissed for the first time. It was beautiful and magical, I was so shocked how great it was that I don't think I had it with anyone else before, not even my 4 years ex (when we kissed first time). Anyways, we have been seeing each other a lot and enjoy each others company,and yes we have and is great. ( please, no judgment here) he came over last night to sleep over, before we slept, we were getting really intimate and during , I couldn't finish because i don't know, tired? suddenly not in the mood? and the cramps just killed my mood..>.< I just sat up and told him "I can't do it, (my ex name)" without thinking at all! I was soooo shocked of what i said, and hoping he didnt hear it. ofc he asked me "you know what you just said to me?" I was trying to playing it off because I was so shocked that it happened and I wasn't thinking about my ex AT ALL! like he doesn't reminds me of my ex, hes not a rebound, i actually like him. He got sooooo mad and got up and left my place and so far hasn't replied any of my texts or calls. I feeel TERRIBLE because he probably thinks he is a rebound which he is not. Will he forgive me? :S i know if i was in his shoes, i would be sooo pissed and hurt....do you think I should give him space? try to talk to him? i dont know helpppppppp :(