Is little blood in discharge counted as the first day of period or not?

Women's health
1

Hello, I need to do a blood test on the 21st day of my cycle. However, I'm not sure which day I should count as the first day: - Yesterday when I had proper, normal bleeding or - the day before when there was just a little blood in my discharge, but no bleeding Thank you!

2

i count the day where theres any discharge only because my period starts like that ill barely get blood the first day

3

Thank you!