After getting my iud out while my period was normal, I didn't ovulate 3 months. Just give your body a few months to straighten itself out, all will be well.
Mine wasn't copper, it was the plastic with hormones. I guess the lack of hormones in copper would change your experience.
Give it until you are 14 days late and test again. Then if your doctor still isn't willing to help you, I'd find a new doctor.