Sex & pregnancy

Is sex safe during pregnancy? I have not been having sex with husband but i have the strong urge now. I feel sexier and my husband keep complimenting that i look more sexy now. My boobs are big but during pregnancy its fuller and bigger and my butt are rounder too. Im 5mths pregnant now. I did masturbate on my own and i had this lower abdomen cramp after that but no bleeding. So now im afraid to have sex. #1stimemom #firstbaby #1stpregnnt