I've only had the Nexplanon Implant for 8 days and up until now my period has always been on time. Never one day late or one day early but today it is 5 days late. I understand one of the most common side effects of the Nexplanon is a change in menstrual bleeding but i was not expecting any changes this soon. Should I be worried that something is wrong with the implant or that I may even be pregnant?