Is it possible that you are just ovulating late and that is the pain you were feeling? If the pain percists I woul get ahold of your gy ecologist and ask for a transvaginal ultrasound and an appointment. I hope it isn't a cyst and just ovulation pain!!
if you only have pain since yesterday its hard to know ,my symptons were on going over a year ,but just got worse i cant really say because everyone is different if your not sure its best to go to gp i had symptons of appendix as well they dident know at er untill they put a camera in but hell advil wouldent kill this pain hope your pain dont last x