Hi i got off my period this week monday, and now i'm bleeding again, what does it mean? i had unprotected sexual yesterday with my boyfriend 4 times

Vaginal bleeding: Any abnormal, unexplained vaginal bleeding requires professional attention. There are many causes, including hormonal (e.g. oral contraceptive dose), pregnancy, miscarriage, and various infections, including STDs -- especially if bleeding mostly follows sex (i.e. post-coital bleeding). A lot depends on details that can only be sorted out professionally. See your doctor soon. Good luck!