Wow that's an old girl. You are doing right by her.
I had an old snake who passed away recently. I have noticed a few minor changes as he got older, from strike/coil his food to just eating it as you hand it to him. I never had that problem that you described.
If your snake is showing signs of not eating or other symptoms including lumps and bumps around the jaw area, something may be brewing in there and an x-ray will be needed to confirm what's going on. If you want to be extra cautious and take her in to the vet now, that's fine too. Understand that they might have to put her under just so to take the x-ray if she won't cooperate at the vet, and that in itself can be risky due to her age. And let's say they did find something, due to the location, there may be little you can do and again, putting her under may not be feasible. The best treatment I think would be antibiotics to stave off any potential infection from the little cut she made. Again you can wait and see or treat it preemptively.
There is a free vet online chat in Chewy website. I don't know how it works but it's something. Also, there is a Facebook group where you can post questions to vets. Please note that only veterinarians are allowed to respond and comment on the posts. You are not allowed to bump or repost if they didn't get to your questions at first try. These veterinarians volunteer their time to help people with non-emergency situations.
https://www.facebook.com/groups/3374...048/?ref=share