Tail issues :(

[Wartortle]

My baby cherryhead has some odd growth/infection I don't know on his little tail. It's all white and squishy. Thoughts? Has anyone had this happen? I'm planning on going to the vet tomorrow afternoon, but if I can prevent it then I'd prefer to do that.
(see picture)

 

[crimson_lotus]

Weird. I can't really tell, just want to make sure - is that on the tail or coming out of the cloaca?

 

[Lexiii]

Please update us after the vet. I am dying to know what this is.