There's not many things that are happening at boot: the UEFI Boot Manager points to GRUB which boots your system.

It's almost certainly one of them. The Boot Manager's entries can be fixed with efibootmgr

Most likely you'll also have an issue after it boots because of the swap from being on /dev/sda to /dev/nvme0n1. Your home directory or swap file from the USB drive probably in the fstab like:

/dev/sda3     /home    ext4    options   0 0
/dev/sda4     /swap    swap    options   0 0

Now /dev/sda doesn't exist anymore, because you're on an NVME drive. Now those directories will be at /dev/nvme0n1p3 and /dev/nvme0n1p4. You'll have to edit fstab manually to fix this. If fstab is using UUIDs then it'll work as-is since the partition UUIDs would have been part of the image.

e:

Obviously that’s not the exact dd command I used, for privacy reasons.

Unless you did

dd /dev/urandom /dev/nvme0n1

Then you're probably fine.