Could this have been implantation bleeding???

I started with brown discharge last Monday that was like a light spotting never required a pad only a liner to keep the spots off my underwear. My period was due yesterday and hasn’t shown up yet. I never get spotting mid cycle and this was way too light to be an early period for me. I go to my doctors office Tuesday for an appointment about the irregular spotting but just wanted to know if anyone else has experienced this and what was your outcome?