Missed period for five days

I took my nexplonon out five months late and up to that point I had my period regularly. I decided to go on the pill instead and my doctor told me to wait until the first day of my next period to start it. My period has now been five days and part of me is still thinking it’s because of removing the old birth control but another part of me feels that it could mean I’m pregnant. Anyone experienced anything like this before. I’ve already decided that if I still don’t have it in a few days I’ll take a test.