If the pains are to severe you cant deal with them, you should see your doc. BUT most likely it is your ovary getting ready to release an egg. Clomid stimulates the ovaries, and since you are on Clomid it is obviousely becuase you were not ovulating, so stimulating your ovaries to release an egg after a prolonged amount of time can hurt, and cause pain. Just keep checking your discharge, and when its slippery and clear thats great. So good luck.
If they are truly "severe," then you need to contact your doctor. Review you patient information, or look up clomid on WebMD, and it will tell you this. I think severe pain can be caused by hyperstimulation of the ovaries...It's early, so I'm not thinking straight, but look it up on WebMD and read about cautions and side effects.