Expander, Braces and Retainer 8 yr old

So my son had issues with a cross-bite and his adult teeth coming in wonky. We opted for early intervention and had a palate expander and a few top braces. He is 8 and had the appliances removed after for 7 months. He was fitted for a retainer and we have to wait a week for it to be delivered.. It's been 5 days and I noticed a gap between his front teeth. So his teeth seem to be shifting. Now I did ask the orthodontist yesterday and they said it is fine, the retainer will close the gap.. But the gap seems to be slightly bigger every morning.. Has anyone ever experienced this before? I know his ortho said it was fine but it would be nice to hear it from anyone who has experienced this.. thank you in advance!

It will be fine. When in doubt, trust your medical person. Also, there’s nothing you can do in the next two days, at which point, the retainer will be in your hands. We had to do the same two-stages with one of our kids, and it worked out fine. Good luck with the process!

Teeth move around quite a bit.
His smile will be perfect before they finish.
You just have to be patient.