I started taking Loestrin24 Fe in July...At this point I'm on my ...

I started taking Loestrin24 Fe in July...At this point I'm on my 4th package....The first 2 months, I missed my periods (even though I had some bleeding but not when I was taking the placebo pills). I would usually get some bleeding on the 2nd of week of active pills. My third month was normal, I was so happy. Unfortunately, now I am on my 4th pack and 15th day onto it, I have some really heavy bleeding with terrible cramps (cannot deal without taking pain killers). Today is my 3rd day of bleeding and really bad cramps which makes me really scared.....Don't know what to do...Any suggestions???