Hi there,
Are you using Merina?Merina can cause menstrual irregularities and cramps but these effects are common in the first few months of its use. The hormonal IUD can cause noncancerous growths like ovarian cysts in few women. These can cause abdominal pain and spotting in between. The chances of ectopic pregnancy are increased with the use of IUDs.If you are doubtful about pregnancy take up the test. This is merely an advice. A clinical examination may be necessary for appropriate diagnosis and management of your condition. I hope it helps.
Best luck and regards!