Hallow Dear, I have understood your situation and problem. Whenever a period is missed in childbearing age, pregnancy should be ruled out first. Moreover, you are having nausea and other gastric problems. Please keep in mind that iud prevents only the intrauterine pregnancy and not the pregnancy outside the uterus. Hence, whenever one misses a period with iud fitted in, we first try to evaluate the woman for ectopic pregnancy. The other possibility is pregnancy with iud which is a rare incidence. Also a possibility of migration or expulsion of iud is to be kept in mind when pregnancy can occur. Of all these possibilities, ectopic tubal pregnancy is a very serious condition and when ruptured, may cause alarming bleeding inside the abdomen. Please do not waste time and report to an Obstetrician to pinpoint the diagnosis and help you. I hope you have got proper guidance. Ultrasonography may help you to diagnose the condition.