My Boyfriend And I Have Been Having Unprotected Intercourse The

My boyfriend and I have been having unprotected intercourse the past few days, he did pull out during ejaculation. He did breach my cervix and my last period was ended almost 2 weeks ago. We last had intercourse yesterday and today i started having a light brown discharge, accompanied with light cramping and "butterfly"type feeling in my lower abdomen, also it does have an off odor to it. Before this weekend it had been over a month since my last act of intercourse and protection was used. Should I be worried?