6 dpo - I’m starting to see hairs attached to white stuff at the end start to fall off after shampooing, should I be worried ?

Thanks for the question and pics. This looks very normal. As the skin heals around the grafts, the scabs will start to fall off and take the shaft of the hair above the surface with it. The root of the hair is still underneath the skin and will start to grow around 3-4 months after surgery. Keep following your doctors instructions and for any concerns make sure to reach out to them. 

If you are concerned please follow up with your doctor for an exam.
Most patients experience shedding. You will have hair loss after surgery. You may have graft loss after surgery. Not all the grafts will take. You won't really know until you see results in 6 to 12 months.

Shedding can start as early as one week. Washing your graft area is very important to keep the crusts off