I suggest that you schedule an appointment with your OB/GYN. As you probably know, the most common cause of a missed period (especially for greater than 2 months), is pregnancy. Whenever someone who had normal periods suddenly stops having normal periods we call this problem secondary amenorrhea. There are a few possible causes for this problem. In your case, it sounds like you are experiencing other symptoms other than just the lack of a period. If you have a history of having your uterus instrumented as with a D&C then it is possible that you developed some scar tissue there that has prevented you from bleeding
out the cervix. This problem results in cycles continuing but without the visible bleeding bleeding leading to the belief that there cycles of stopped. Another possibility is that you might have polycystic ovarian syndrome. This is a syndrome which affects multiple areas of the body but often results in problems ovulating which can result in longer cycles without menstruating. Some of your symptoms including breast soreness and abdominal discomfort might be consistent with polycystic ovarian syndrome. Again, I would suggest that you schedule an appointment with your OB/GYN. He or she will likely want to perform a detailed physical exam and also will likely want to perform a pelvic ultrasound
. The pelvic ultrasound is designed to look at the uterus to make sure there's no scar tissue and to look at the ovaries to see if cysts can be seen.