IUD - Late period

Hi everyone! I had my IUD (Mirena) removed in early February. I then started my period on Feb 11th. I had it for almost 3 weeks then had intercourse on March 4th, is I think we missed our most fertile days. But I am currently 2 weeks late and have not started yet. I've taken test and keep getting a negative. I did have some good cramps around the day I should've started March 11th but it only last a couple of days. Has anybody else had issues getting a regular period after an IUD removal? I'm never late as my periods are very regular at 28 days. So not sure if I should see a Dr to get blood test or just wait for period to start. Any suggestions or opinions? Thanks!!