Cried during sex.. bad

Yesterday I was at my bfs house, and all the sudden we were going at it and I started crying. I don’t even know what happened. I just said “get out” and he thought I was playing so he looked at me and said “what?” Then kept going and all the sudden I was bawling. It was like I had a full on mental breakdown but it only lasted a few minutes. Not to mention I broke him because he didn’t want anything today and he was saying how he didn’t want me to cry. As it was happening he hugged me and all I could think to say was sorry, but I feel so stupid. Is this normal? Or am I like total fuckup?