I'm on the pill and I was wondering if your pms symptoms can change due to missing pills, being on the pill for an extended time or anything else? bc I'm suppose to start my period today and I've been on birth control for a year now and I switched my type of pill once, and I never would get cramps on the pills before the ones I'm on now, and this cycle I am not expierincing any pms symptoms. Any advice or explanations?