Will shaving before the 2 week mark where shedding will occur have a negative effect on the hair falling out?

The energy from the laser is entering your skin and targeting the papilla (hair root). Shaving does not effect the papilla, so it has absolutely no effect on how much hair will fall out and how much will remain. The important thing is to not tweeze, wax, or use any chemicals that will remove the papilla while you are having laser hair removal treatments. You can shave as often or as infrequently as you like.

I agree with Dr. Dickerson, shaving after laser hair removal has no effect on the outcome.  However, depending on the sight, shaving one to two weeks prior to the laser hair removal treatment can actually improve your outcome.The papilla with be thicker and have more contrast from your skin in the mitotic(growing) stage which allows it absorb more thermal energy from the laser thus destroying it.   

Thank you for your question. Shaving after laser hair is fine to maintain the area between treatments. You must avoid waxing and chemical depilatories such as Nair. Best Wishes,Pablo Prichard