Anorexic axolotl???

hello!
About a week ago, I had rescued an adorable little axolotl! It's my first time owning one. I've done my research and reading prior to buying him food and setting up his tank; I have the water at around 18 degrees Celcius (its been treated for ammonia and the likes of course).
I'm trying to feed him bloodworms and these pellets that were given to me when I rescued him from previous owner.
The problem is this. When I rescued him, he had swallowed a few pebbles that must've been in his tank before. So I waited and about 2 days ago he pooped them all out. I had bought bloodworms that same day and tried to feed him. He'd been in the tank for a while so I thought he would eat. He went for the bloodworms but didn't seem to swallow them and I'm not sure he actually got anything in. Now since he's pooped all the pebbles out he looks very skinny, I'd say anorexic, and he's not eating at all. He walks/swims around a bit and it looks like he's very slightly floating; like he's not heavy enough to stay down properly. He won't eat and I'm concerned at how terribly skinny he looks. I don't know what to do!

Did you cycle the tank before adding him and have you tested the parameters? It is good to ensure good water quality to rule out issues with water quality and to ensure he has the best conditions for recovery.

Axolotls will sometimes not eat when they have just moved to a new home so he may be adjusting to his new home. He may be feeling quite weak also if he is super skinny and there may be other factors especially not knowing his history from the previous owner. Could you post some photos?

I would firstly check your water conditions and ensure he has good water and keep persisting with food. Maybe offer some different types of foods? How big is he? Earthworms are a more nutritious option for a staple diet and would be a good option if he will take them. Make sure they are from a garden where no chemicals have been used (ie fertilizers or pesticides) or purchase them from a bait store. Another option may be to try scallops? I have not tried these myself but have read that these can encourage an axolotl to eat. They are not ideal as a staple diet but at this stage it may be worth trying to encourage him to eat.

Axolotls respond to motion. See if you can get its attention by waving the bloodworms above the head,. If it is an adult and completely avoiding food, I'd force feed.

I haven't tested the parameters, but ive heard about some kits you can buy to test them yourself? or would you recommend to get a shop to test it for me?
He seems less skinnier than before but he still hasn't really eaten and is still swimming around a lot.
If he east the earthworms, can I continue to feed him these as an every day diet?
He's only a very small thing, i'll post some photos

The only pet store where I live had no idea how to test the water correctly and obviously just made up stuff to tell me... Hopefully not all are like this but since having your own lets you test any time you want it is much more convenient. A liquid testing kit for the three you really need (Ammonia, Nitrites, and Nitrates) ran about $30 here in the US and includes pH as well. I have heard the paper strips can be very inaccurate and that liquid is worth the cost.

Earthworms are a very good food for them. I occasionally get nightcrawlers and chop it into bite sized wiggly bits for my juvenile and he loves it.

Earthworms make a great staple diet so yes you can definitely keep feeding them. I would maybe chop the worms into smaller chunks for this little guy given size and being quite skinny. Some axolotls don't like red wiggler earthworms so you may find it better to try other types of earthworms. European night crawlers are good.

You should definitely have your own testing kit. Get a liquid test kit for ammonia, nitrite, nitrate and PH. Avoid the test strips as they can tend to be inaccurate. I use the API Freshwater master kit. It is easy to use and comes with instructions. Your tank is most likely in the process of cycling so it would be best to get a kit as soon as possible so you can monitor the parameters closely. Post the readings here .