I take birth control regularly, can I be pregnant?

[hulagirllll]

I never miss a pill. I've taken them about 1 hour late but never miss any. When I wipe the past couple of days, I've noticed a miniscule tint of blood in my vaginal discharge. BUT THIS ONLY HAPPENS AT NIGHT, nothing during the day, not even discharge on my underwear. After the first time I noticed it, I kept putting my finger in to see if I was producing more discharge (in case I'm going through implantation bleeding) but my discharge have been very minimum and nothing abnormal. Could I just be irritating the wall with my finger/nail and causes this tint to appear? My boyfriend and I haven't had sex in 3 weeks, although the last time he went in raw but we put on a condom not too far into the act. I had also just gotten off my period for a couple of days. I've checked my cervix as well and its sitting pretty low, I think. My finger doesn't have to go very deep to feel it. I'm so nervous that I may be pregnant, I just need reassurance.