I'm 18 years old. On 01-05-2015 I started experiencing signs of my period. I had mild cramps and when I wiped I saw a brownish type blood. So automatically I thought my period was on. For the rest of the day I checked and checked and no other signs of my period. Blood wasn't even on the pad. So on 02-05-2015 I had unprotected sex with my boyfriend (I'm not on birth control). He didn't ejaculate in me, but I don't know if he pre cmmed. For the next couple of days I've been experiencing off and on spotting of the same brownish blood and one time it was even watery. Some days it would be on the pad and other days I would only notice it when I go to the bathroom and wipe. Sometimes I even have mild cramps. What should I do? Has anyone ever experienced this before?