Few queries from my side..
1. Are you tubectomized or using any other contraceptive
2. Is there any weakness or losing of weight?
3. Is there any fever or vomiting
All these are to rule out an ectopic pregnancy
in case if you are having active sexual life.
If not, could be a PID which is a inflammatory disease.
The discharge could be because of ovulation but pain shouldn't be ignored.
You can get an ultrasound
scan done to know the diagnosis which can be treated accordingly.