i used to have the same problem,every time i would shower i would notice so much of my hair clogging up the drain and i thought it was normal then i switched shampoos and conditioner,i changed to matrix colourcretherapie shampoo with acai berry extract and rusk sensories leave in conditioner,also i got a wide toothed comb and now brush my hair from the ends and work my way up gently to get knots out,u may also not be shampooing your hair correctly,go to youtube and look up Farah Dhukai or go to dhukai.com,she will show u the correct way to shampoo your hair and has diy remedies to stop hair fall,i swear farah dhukai has TOTALLY changed the condition of my hair and i have next to no hair fall because of her,i cannot recommend her enough shes the bomb!!xx