Urgent advice pls

I am 16 years old (nearly 17) and I have been having problems. I came off the pill about a month ago and I still haven't got my period. It's been 5 days late so far. I have been having sexual intercourse with my boyfriend ALOT in the last month with no contraceptive or anything. But my boobs have been so sore and swollen for about 4 days, and my lower tummy has been so sore and weird as. I'm still seeing discharge in my undies which stops two days before my period. I just don't feel like I'm getting my period. And I've been feeling weird and really hungry and feeling like I have no energy and my lower back has so much pain. Is this pregnancy? My period coming? Or just coming off the pill?