my last period was December 15th have had sex prob like every other day since. i thought to believe i was pregnant, sore breast, moody and period was a week late and i I started bleeding lightly during sex, so I put on a pad and its been hours later and no bleeding only a little when i wipe and its like a light pink color. Slight cramping and a little pain in my left side but went away after a few mins or so. Should I be worried?