The number 1 side effect of the paragaurd is heavy menstrual bleeding. As long as you stay hydrated and your strings are there you should be good.
Thanks(: I checked and everything is okay down there. The only thing that had me concerned was the fact that I went through 14 pads yesterday due to heavy bleeding. And today its somewhat lightened up.
What you're experiencing sounds normal. I also panicked whenever I had any unusual pain after Paragard insertion. One thing you can do is feel the threads and see if there is more length than before. You can also check your cervix to see if the bottom part of the IUD is being expelled. If not you're probably ok, but if you're really concerned, go to the GYN. I wouldn't think an ultrasound would be necessary unless you're bleeding profusely.