I was diagnosed with endo last year and had a miserable time until I went on birth control. It worked amazingly for about 6 months - no cramps, nausea, fever, stomach issues. But for the last week all my symptoms have come back even though I'm still on the birth control as usual. I just started taking the pill continuously and haven't had a period for two months but I don't see how that would affect things. Is it normal for birth control to suddenly lose effect?