Hi Im 16 and Me And my boyfriend have been having unprotected sex.well around the time i was suppose to have my period i had some dark brown blood but hardly any came out and this lasted for 4 days.this isnt normal for my periods i usually have very very bad cramps!! && heavy red bleeding.but this time it was dark brown and no cramps at all but it was hardly no bleeding at all.im kinda worried can anyone explain why This happened????????????