I've Been Taking Minastrin Birth Control And I Recently Had

I've been taking minastrin birth control and I recently had to refill my prescription but it took a long time to get it so I missed four days of my pill but I took it when I immediately got my pills back. I've had my period for two weeks now and it hasn't stopped. Is this normal? Also did the four days affect the contraceptive ? Am I at a greater risk of getting pregnant?