18F, I have lots of small white hairs with black bottoms falling out - why?

recently I’ve seen small hair falling. It’s thin and white on one side and black on the bottom. looks like breakage I’ve never had white hair before I’m too young. I got diagnsoed with TE and I’ve lost some small thin hairs too, and my TE stopped now after 3 months. Some 1-2 inch hairs are falling too but they’re thick. And, a lot of white hairs on top and black on bottom hairs are falling one had a bulb maybe in the white part but I didn’t see well because it’s lost. Why?