sorry im at work so cannot type Chinese.
I think it is very normal. It sounds like just slightly heavier discharge. If not smelly, not painful, no fever, no problem. You should ask a doctor or nurse to check your IUD in 4-6 weeks time, to make sure it is sitting at the right place. Don't worry too much la.
Very normal heavier discharge, heavier period, longer period and more period cramps with IUD--because it was no hormone~