My boyfriend and I have been having unprotected sex once and a while. The last three days I have had bad cramping after sex, tender breasts, and today late in the day I had a light spottiing period, but not like my usual. I'm usually a heavy flow and I've never gotten my period towards the afternoon, always in the morning. Could I be pregnant, or should I go to a ob/gyn to check for a cyst or PID?