So ive just had 1 of those moments where u think uve sused everything out.. here goess... Usualy my cycle would be like textbook 28 day cycle obvulate day 14 etc.. BUT i had the implant and after removal i had period exacly 3weeks after. Ive had possative pg tests at home, went drs and they said negative (just pee on a stick, no bloods).. Im wondering if my cycle has changed now too 3weeks (21days) it would all make sence. As that would mean a few days after my last period finished i would have "concieved". as i got my first Bpf on the day i would suposidly obvulate on my usual text book cycle, which would also mean im now 3days past my period ( in theory, on this 21day cycle) other wise due period in 4days. but it does fit :D Sorry if anyones confused. basically is it possible for ure cycle too change? i had implant fitted after my 1st was born, and had that 1 period 3 weeks after removal & now thiss.... :)