Just stopped birth control... discharge and severe pains?

I just stopped my birth control a week and a half ago (i plan to go on it again after this next cycle), but starting 2 days ago, I've been getting lower abdomen pains (feels like ovaries, but im not sure), but when I walk it kills, especially when I walk up stairs or walk in heels. I have also gotten a LOT of mucus/discharge, like a nickel size of a weird yellow-y colour twice or three times a day. I can't be pregnant, I haven't had sex in months. Does anyone know what this can be ?