Axolotl thrashing head around.. how to treat?

Hello I have a male axolotl almost in his adult stage I believe. Over the last week he seemed to have been loosing some gills, (no tank mates) acting funny and almost seeming to be trying to jump out of water. So I did a test and my water quality was horrible. so after I did the perimeter test i freaked out (not having a pump after my dogs chewed it up recently🤦) and put him in a container and dumped all of his water out and put %100 new cured water in his tank. At first he seemed to be doing much better but now he s thrashing his head around like never before and it s like he s trying to scratch his gills or something. I see no visible wounds so I did some reading and I m worried he could have either ammonia burns or fungus. I know these two problems have completely different treatments so I guess I just need to know if I should try a salt or tea bath first? I just dont want to put him in a salt bath and end up hurting him or making the problem worste.. HELP PLEASE