What should I do?

I’m 8 1/2 months pregnant, I just worked all day and I work at the same place as my boyfriend. We already have 2 kids together. We were laying in bed playing with them because my legs and body are sore from working and I jokingly accused him of checking out a girl today (which I saw him look her up and down) he screamed no I fucking didn’t and punched me as hard as he could on my leg, it was in anger, he WASNOT joking and said ‘I didn’t know your leg was there’ it hurt pretty bad so i started crying also because it hurt my feelings.