starting the pill early

i started the birth control pill a week before my period was meant to start as i was taking it to clear up my skin(i get afew spots on my checks during the few weeks before my period) i have been on it for 3 weeks now and finished my first packet yesterday i started a period with 4days left on the first packet now 5days on my period is quite heavy. i havent given myself a break because i thought it was best i carried on with the next packet to control this period i am having now.

i am quite worried i dont normally have a heavy bleed and its lasting longer than usual.

also my skins gone worse.