Red spot on my axis mouth (help please)

[lammaloo]

I have a 3-year old female axolotl that has gotten a red spot on her mouths left side and I´m starting to get a little worried. I´ll stich some pictures that I took yesterday. I have seen her have a red spot before but I just thought she had bumped into something but it has gotten worse. I also saw that she's some type of silver ish colour on the underside. If someone has some knowledge about this please comment. I have tried to look around on the internet and the closest i could get to something was ammonia burn, but I´m skeptical. I also saw somewhere that I could do some sort of salt bath but I don't know what that bump is so i wanted to ask first. If someone know about this I would really appreciate it!

 

[wolfen]

the lump looks like an injury, possibly from snapping at something it shouldn't.
the metallic area is possibly due to iridophores (which can also be seen on other parts of the body).
salt can be used to aid healing but not at the levels that salt baths are (high levels of salt are very stressful), use 2g/l non-iodised in her water, can be increased to 3.5g/l but shouldn't need to be, if the swelling increases or any abnormal signs are displayed see a vet for antibiotics (shouldn't be needed but incase it is already infected will be required).
how is she fed? if using tweezers or tongs care may be needed.
always regularly test water parameters even when sure they are fine.

 

[lammaloo]

Thank you so much for the feedback, yes I do give her worms with tongs and she's always fast so she touches the tongs sometimes. What is iridophores and are they harmful to her? And if i would like to put salt in the water how do I do that? I also have a another axolotl in the aquarium but they are separated. I looked at her lip just now and the redness has gotten down. But underside of the lip where the metallic color was has gotten quite dark.

 

[wolfen]

iridophores are reflective patches of skin which are quite common with axolotls.
it is easiest to add salt at a water change were it can be dissolved before adding to tank.