is this the non hormonal coil? if it is then it shouldnt give u side effects, when i had mine (non hormonal) my periods were so light, i had no side effects, except i felt i gained weight which in theory shouldnt happen as there are no hormones. Coils come in different sizes, maybe yours is a bit too big, and u need a shorter one fitted. coils list side effects as having heavier more painful periods butb i found the opposite, so see your family planning clinic, not your GP as the clinic will have a full range to suit you