Yeah the scrubbing too hard is what I was thinking about me too. And I would detangle before my hair got seaweedy. I figured that out after a few days though.
I'm not sure what it was but I hope it doens't come back. My hair is def thinner. I was like you, fine hair but lots of it.
When I wash now though just a few hairs will shed so whew I'm back to normal yay!
Low porosity, medium texture.

If it smells good put it in your hair, if it tastes good spit it out!