Period late after IUD expelled itself Negative HPT

My hormone-free IUD (Paraguard) came out on its own for the second time on the last day of my last period which started on 11/19/2019. This is the second time this has happened to me, I had it in place for 4 years and the previous one was in place for about 1 year. I have always had regular 28 day cycles. I am now 6 days late as of 12/22/2019. I have had PMS symptoms the last 2 weeks like cramping and tender breasts but no period. I took a couple HPTs and they were negative. Has anyone experienced this after Paraguard removal and if so when did things return to normal? What would be the cause of a change in a cycle if there was no hormonal change? Any input or similar experiences are welcome!