Pushing the bike BACKWARDS...Is it harmful to the motor?

Hello,
So I just received delivery of my Prime (pictures soon!). When I push the bike backwards, the motor makes a clicking noise. Just wanted to know:
1. Normal?
2. If normal, does it damage the motor by pushing bike backwards? (Yes, I know bikes are supposed to go forward, but I mean like rolling it back into its parking spot!)

Can't wait to ride. Still finalizing set up (brake adj, gear adj, etc)

TIA