need advice!

i’m having exact period symptoms 2 weeks early from when i am supposed to be having my period on lo loestrin fe birth control however i’ve been taking this pill for 4 months and haven’t gotten my period (dr says it’s fine) but i’m having normal bright red blood shed and cramps and i don’t know what it could be. i’ve never missed a pill and i have had sex but i don’t think i am pregnant