Could I be pregnant?

I'm on birth control and take it for 3 weeks before I have a week 'off' when I have my period, then go back to taking it etc. I haven't changed the pill I take and have been taking it since I was 17, so over 10 years now.

In the past 2 cycles, I've had pink spotting before brown discharge.. I'm in the middle of cycle 2 so don't know if this is what's yet to come, but last time I had a really heavy period - I'm usually mid to light flow, but went through 4 ultra tampons and 4 large pads in a day, I'd usually only need 3 super tampons (I use Lilets if that helps) and no pads. Last cycle I was days away from my week 'off' the pill, this time I'm just over 2 weeks in.

I know it's not exactly responsible of me but I don't use any other form of protection with my boyfriend, but we are on a huge trust basis whereby if I'm on my period (for mess sake) or something isn't right - with either of us, we don't have sex.

I'm scared to do a pregnancy test, but just wanted to know if anyone else has had the same and turned out to be pregnant or not? Not really getting a definitive answer online before people telling me to 'just Google it'!
Updates
+1 y
I maybe should have added - my periods are usually like clockwork! So this is the first I've had irregular bleeding!
Could I be pregnant?
Post Opinion