2nd fue to add density to 1st procedure. First fue hairs now shedding! Will they return?

You can have shock loss after surgery.  If you are concerned it is best to contact your doctor for a follow up exam.

This is just shock loss the the transplanted hair from the first procedure. They should grow back within a few months, nothing to worry about.

Sometimes, there might be a loss of hair in the transplanted area because of the shock loss. However, they usually come back in 3-4 months time following surgery. it will be better if you can confirm this with your operating surgeon.

yes it is a transection of preexisting hair because of slit making with micro blades... but fortunatelly it is not a permanent hair loss.2-3 months after surgery , native hair also starts to regrow again and heal well .

Shock loss is common, even with transplanted hair, post operative in both the donor and the recipient area.  Be patient it should return.

This is not uncommon and you should not worry about this. The blade used to create sites can cause this but the hairs there usually recover nicely. Be sure to follow up with your surgeon and let him or her know your concerns. 

It is not clear what you are worried about. If you really are concerned, go back and see your surgeon and ask about it. Shedding of previous hair transplants are unusual