Bleeding still... Whyy?

Since I was 16 I've been on the implanon. Just out of caution, not because I was a 16 yo nympho. I'm almost 21 now. Long story short I was sporadically bleeding & got myself checked out; chlamydia. Myself & my bf got treatment, & I was put on the Pill to regulate bleeding (my understanding; make it stop again completely.) It was going so well! No more pain during sex, no more blood, everything was great. Then I woke up this morning with a motherlode of blood. My lower abdoms hurt the night before, they hurt again tonight (it's not an unbearable pain but still uncomfortable) so I'm expecting more blood tomorrow :-( Please help, I've no idea. Doc told me last time to get another appointment in 3 months, I still have 2 months & a bit left... I need help to put my mind at ease if anyone can help?