Birth control question?

ok so this is kind of weird, but my moms not in the picture so i don't know who else to ask. ok so about a month ago i started using trinessa birth control, and i started on the first Sunday of my period, just like it said. well since then ib been getting occasional brown blood clots, like blood during my period, but brown. is this normal, its been going on every since i started the pills. also, i didn't realize until yesterday that my birth control expired on July 12th. im lost here.