It is abnormal to become pregnant with a IUD inserted?

you are definitely not he first. your biggest decision is going to be to decide whether or not to get the IUD removed. if you get it removed you risk a miscarriage and if you don't it could cause your water to prematurely break. you will most likely have to discus this with your Dr and have an ultrasound. and you should be mad about him not believing you! but give him a little time to process this he was obviously not expecting this. good luck!