Not growing; swollena cloaca

Hi, I am desperate for some advice on my axolotl.

My first concern is that he has a swollen cloaca. I originally had a very fine gravel as substrate, not sand, but also not the larger gravel. I noticed his cloaca was swollen and decided to change his substrate to river stones and did a complete water change. He still appears to be healthy and active, swimming around as usual and eating. Is there any suggestions for this? Is he constipated? It's been almost two weeks since I changed the gravel and I haven't seen improvement in the swelling.

My second concern is that my axolotl grows extremely slow. I got him as a tadpole in December 2013 so he is about 3 years old and just under 5 inches long. He has more than enough space in his tank to grow, but just doesn't.


Help!

Here are some more pictures

The redness suggests a bacterial infection - you need to find a vet and get some antibiotics.

If it was my animal, I put him in the fridge
It gives you more time to organize things. Sometimes they get better in the refrigerator.
Bacteria grow poorly or not at low temperature. The Axo in the refrigerator can sometimes build up resistance to bacteria and refurbishing again.
You have to observe him well. It should not be worse, if so then you have to take other action.
(Axo's sick! it is often a water quality problem: way too small filter, aquarium decor with fake plants, Incorrect filtering and ……………… Whereby a balanced system is not possible. And so in order to retain a certain quality is a constantly change of water required. Forget this a few days and you've got a problem.)
The Axolotl will not grow any further. Probably not much to eat during his youth.

I do not know much. Ask others for advice.

Thanks for the suggestions! i have found a vet in my area that deal with axolotls. Will be making a trip soon. Is there anyone who knows the best way to transport him without stressing him out too much?

Maybe put a lot of silk plants in the container you use so that it won't bump around too much.