Haiz, Istihaazah & Nifaas

Irregular discharge

Q: I had a problem of irregular discharge. I used to experience yellow discharge almost every day. Depending on my previous habit, I used to count my tuhr days as 23 and my period days as 8. Last month, after my period ended on 29 January. I experienced discolored discharge on 30 and 31st January. Then I was totally clean for 15 days. After that I started bleeding on 15 February. I counted it as my period. And it ended on the 10th day on 25th February.

1. Was it correct for me to count my period from 15 February?

2. What will be my new tuhr habit and period habit?