My head is itching so excessively that I keep scratching it even though I'm conscious of it.

Even though I wash my hair every day, my scalp feels excessively itchy. Just in case, I tried using anti-hair loss shampoo, and thinking it might not be cleaning thoroughly, I even bought a product to mix with shampoo. It seemed to have a slight effect, but only for a short time, and the itching returned, which is frustrating.

I keep scratching my head, and it seems like my hair is falling out easily and my scalp looks a bit shabby, so I'm worried.