Okay i'll try to explain this as best as I can .

Okay I am sexually active , the last time I had sex was on Monday, May 6th .

It was unprotected but he did not ejaculate inside of me.

My cycles do vary from 24 days to 27 days or 18 days , etc.

My last period was April 15th & I expected it on May 9th but like I said my cycles vary and I had heavy bleeding today (May 15th.) but as the day went on it got lighter & turned into spotting . Idk if this is implantation bleeding or what , I highly doubt that I am pregnant, and I know the only way to find out is a test but I'm only 15. Blah someone help >_< could this be the changing of my period or something ? Or my cycle?