Stressing about my period changing

I have a regular cycle about every 25 days that starts with about 3 days of heavy flow and then two days of medium to Light Flow. However, this month my period started with a tiny bit of spotting, not even enough to need a liner. And this has been going on for 3 days. I gave birth to my third son a little over a year ago and after the birth my OB doctor said they found abnormal cells in my cervix and has been rechecking me every 6 months since then still finding abnormal cells but no sign of changes good or bad. But now I'm wondering if I need to get checked again since my period is different, or if I need to take a pregnancy test. Has anyone else experienced anything like this? And what was the result? Was everything okay?