Ive recently had a few irregular periods with it being to a week late, in the past im always been on time. the past few months, ive had a sharp pain in my right ovary area right after ovulation up until my period. ive had negative pregnancy test?

The new and sudden change in your period may be related to stress, changes in weight or exercise, or many other possibilities. The pain in your lower right side could be due to an ovarian cyst, but also could be a colicky appendix or other cause. Please schedule a visit with your doctor who may want to send you for an ultrasound exam after a physical evaluation.

Menstrual irregularities are not uncommon and anovulatory cycle is a common cause. If you miss more than two periods it would be time to see your doctor. If you do not wish to be pregnant, use contraception all the time. You may consider implanted contraceptive or an IUD. Consult this site. http://www.nichd.nih.gov/health/topics/menstruation/conditioninfo/Pages/causes.aspx