Birth control confusion

So I started birth control pills 3 months ago (about 10 pills left on 3rd pack). I bled the whole first month taking them which I know is normal. I didnt bleed at all once I started the 2nd pack and the first 2 weeks with the 3rd pack I didn't bleed then all of a sudden I started spotting again. Now i've been spotting off and on for 6 days and idk if this is normal or if I should call a doctor. Any opinions or advice?