From what you are saying, I am assuming that this a complete change from your prior cycles. I am also assuming that you are not breast-feeding if you are getting a fairly regular cycle.
What you are describing is heavy periods
) and painful cramping (dysmenorrhea). There are disctinct causes of these two problems, including conditions such as fibroid
(glands that invade the muscular wall), uterine polyps, or normal changes with age.
While it has been a significant amount of time since your C/S, it is not out of the realm of possibilities that these are problems related to the surgery itself. Here is what I recommend:
1. You need to call your OB/GYN to be examined
2. Ask for an ultrasound
to evaluate the uterus
3. Ask if a CT scan of the abdomen and pelvis would be indicated
Based on limited information, this is where I would start in terms of the thought process. I wish you the best of luck!