Is Pregnancy Possible While On Birth Control Pills?

I m on my last week of bc and have been on the pill for 3 months now. On 11/1/17 I started a real period for about 5 days, but had brown discharge for 5 days before that. Then on 11/28/17 I had light spotting when I wiped and it disappeared after that until the day after and the next day (blood was more like brown discharge then bright red & back to brown). Now it is 12/27/17 and I am 2 days late for my period this month. My bf and I have sex everyday.. I m not sure who to ask since I don t have medical. I an usually able to eat a large amount per meal but now I have to eat smaller portions since my stomach feels fuller and bloated. My breasts have gotten extremely large and I feel nauseous from time to time and feel like throwing up. I have also been very tired this past month and moody. I usually break out before my period and this month has been the worst acne yet.. is there a possibility that I could be pregnant??