Hi Salvador,
Great looking setup but it does look thin I would feed it everyday until it fattens up a bit but really cool colouring.
Axolotls are a member of the Ambystoma Mexicanum family. They are stuck in the larval form and only very rarely morph into salamanders. I think what Jennewt was suggesting is that it could be a member of the Ambystoma family that does morph like for instance Tiger Salamanders which in the larval stage look very similar to axolotls.
You could go back to your garden store and ask them, or make sure that there is a rock for it to climb out of the water if it starts to gulp lots of air and spend heaps of time at the surface of the tank.
I agree with Jennewt it just doesn't have the look of the classic axie but that may just be the thinness.
You could have a look at the gallery section of this site at the other Ambystoma and see what you think.
Good Luck