I'm pretty sure it is normal.
If your DVD Drive D:\ is still pointing at the ISO you used during the install.
Normally after the installation is complete, one goes back to the VM settings and usually changes that to something like the Physical DVD on the host machine.
I may have mounted it without realizing what I was doing last night. Was getting frustrated trying to get it right again after it quit working. What I met by not working was the message it could not find Win 10. That is when I decided to start over again.