Weird Knot on Neck

[Homebody]

clarification: the lump can move side to side and so on - when i said it wouldn’t move i mean, it doesn’t feel like it is something caught in her throat that could be dislodged or something - if she was one of my human patients i would say that it feels like a cyst or something?

A fluid cyst can appear overnight. I know because I have one. Scared the hell out of me, but it turned out perfectly benign. Hopefully, your snake's will too.