6wks pp and not nursing; paragard was placed 6 weeks pp and started cramping and bleeding heavy immediately, should i be worried?

Not necessarily: Paragard can cause bleeding, especially early on after insertion. This will resolve or at the very least dimish in most patients. If you have bleeding that is persistent, you should see your gynecologist for evaluation.

Get it checked: Might be normal, but i would get it checked, make sure it is not infection or other complications of iud.