Sick Axolotl?

[Lyv3wyr3]

I am pretty sure I have a male albino axolotl. About a month ago I noticed what looked like a rock a (he has river pebbles in his tank) in his stomach and he has refused to eat since. His gills have shrunk and he is really skinny everywhere except his stomach. I don't know for sure he ate a rock but I think he did His entire belly area is a dark purple. I know he is going to die of starvation soon, but I was wondering if there was anything I could do to avoid him dying. His water is all clean and he has no signs of infection.