Very light flow

Hello all, hope you doing well. For few months now my period have been getting lighter every time. This month its started with spotting one day before I am suppose to then I had light flow for like day and half then it went back to spotting for 3 days.

Is this normal? I am not taking any birth control and we not trying for baby so we taking our precaution.

I took pregnancy test in case and it was negative. I am not sure if I should see a doc or this normal happens with age and having kids. I am 28 with 2 kids.

Sorry for the long post 😅