Hey Girls, I Need Some Advice!

Basics:

I started my period on the 16th February, Friday. I've been having medium flows Friday to Sunday. Yesterday my flow was really light and today I haven't seen any blood so far.

I wear tampons as I find certain pads uncomfortable, my Mum is buying me some lite ones as even on my heaviest days there is still a ton of white on the tampon.

Question:

Is it okay for me to leave 8 hour regular tampons in for school, I get too anxious to ask the teachers to go to the bathrooms. Most teachers don't let you out anyway. I'm also wondering, why is my flow so light?