Minipill and pregnancy?

I've been on the minipill since early April. My husband and I had sex using the pullout method about 3 days before starting the pill and then still used pullout for the first two weeks of the pill to make sure it was in my system. The second week while I was on the pill I started bleeding very lightly and assumed it was my first period. I am now almost through my second bc pack and have not had another period. I know bc I'm ebf and also in general that minipill can cause inconsistent periods, but is it possible that I'm pregnant again? I don't want to waste $20 on tests but I'm wondering.... I don't know what to do!