I haven't had any children yet, but I have birth control mirena (levonorgestrel) and it's been causing me pain in my lower abdomin. I've had mirena (levonorgestrel) for a year + now.?

Lots of other causes. You will need to be seen by your doctor to determine the cause of pain. Of you had your iud for over a year without problems I would investigate other causes such as an ovarian cyst. The doctor will verify the iud is in the proper location by exam or sonogram and look for other causes as well as test for infection.