Should I wait or test!?

Elizabeth • 28 & happy.

Hi all! I'm 17 dpo, have a copper IUD and 3 days late on my period now. I've been cramping on and off for about 5 days or so. No spotting what so ever. My nips have been extremely tender for over a week. Usually when I'm late the hubby and I have sex and that will help kick start the flow, well we did that yesterday and nothing happened! This is very odd for me. My periods are very regular. Any advice!? Thank you! 🙂