period my periods used to be every 27 days like clock work then i started birth control now i never know when im gonna start its been between 17 days to 36 days. also i never had bad cramps now when i have my period its super painful i can barly do my job. is this my birth control or could i be having a tubal pregnancy because my pain is lower in my pelvic area and in ny stomach i have horrible headaches and i pee all the time my breast are sore a lot