Girls, we had sex with my husband. There were no restrictions from the…

Girls, we had sex with my husband. There were no restrictions from the doctor. On the contrary, I read that to avoid ruptures it's desirable... But now after sex there was a little blood with yellow discharge. Could this be a plug? Or should I call an ambulance? I haven't told my gynecologist because it's 4 am. I don't know what to do.