Spotting between periods. 6 days away?

Hello, am 41. My periods are regular, every 30 to 33 days. I have on and off spring during certain months exactly between 11th and 13th day of LMPand it stops. Like ovulation bleeding. When i say sporting is mostly discharge streaked with very light blood. My LMP WAS DEC 5TH. I traveled by car the last two days for almost 20 hrs and yest I had the same spotting, just once, discharge tinged with blood. Then it was fine. I exerted a Lil that as well while cleaning abd same thing happened after. Can this happen due to stress and exertion? Or because my period date is 6 days away? Also I have a polyp. We are observing it for now. It's 1.0 *0.9 cm for almost 1.5 years now. Last scan was in sep 2022.We have considered removal but did not see any problems yet. So not decided yet. My Hb is 10.8, hba1c is 6, all other tests are normal including papsmear.Please advise. Thank you