Suggest Remedy For Irregularities In Menstruation

Im 24, been on the conctraception pill since i was approx 15, off and on, but mostly on. Ive stopped taking it about 6 weeks ago and been getting a period every 2 weeks that usually last about 3 days off a bright red. Is it normal or should I go to my doctor? last time i came off the pill I didnt bleed for 5 months so I went back on it.