One of my dwarf hamsters has a hole to its bone, by its neck/back area- yo can see it moving, and it's obviously deep- but no blood. It's a small, rough circle, looks clean, no dried blood. It's in no clear pain, eats happily, drinks its water, spun on its wheel and in the ball, and it was only noticed properly when I petted it.
I'm pretty certain I should call the vet, but can it wait until the morning? If it needed antiseptic or something, then I'd pay for it obviously, however small, he's still my pet and needs to be cared for, but can they actually do anything?