Help me!

Hi! Can you help me?! I was on the depo shot for almost 3 years. Got off and started nexplanon. The whole 3 years of being on these 2 birth controls, I never had a period. Maybe spotting but that's about the extent of it. I got the nexplanon removed back in June of this year, however, after being told I'd most likely receive a period within the week or 2, I never did. Now here I am, 4 months later, with a full blown period. I even had a small blood clot..however, I also had unprotected sex approx. 4 days ago. What should I do? Any suggestions on whether it be a period finally after 3 years or is it possible I'm pregnant?