New axie and new axie owner!

After cycling my tank, I took my water sample to my pet store where I got Bowie on Sunday!
They told me that the water conditions are good for him.

I take him home and put him in my tank and feed him night crawlers. I fed him a whole crawler in bite size pieces and then another quarter of another one. He didn't hesitate to eat them.

Yesterday I came home from work and tried to feed him while I spot cleaned his tank. I found pieces of the worm that I fed yesterday in front of my filter... I'm pretty sure he threw them up. I came back after emptying the dirty water and he had a piece of worm in his mouth that I didn't feed him.

He is active and swimming all over in the tank. I'm worried that I did something wrong? Now he won't eat.

Could it be he is still acclimating to the new tank environment or that I overfed him?

What kind substrate did the pet store keep him on? And what are your water parameters and temperature? Pet stores are notorious for getting their ''facts'' wrong.

He was in a bare bottom tank. My tank is bare bottom as well. They didn't test the water the day I got him, instead it was the day before. Ammonia, nitrite and nitrate was 0. pH was 8.2. And the GH was 8 and KH was 12.

The temp before I left for work this morning was 64.

He's also 8 months old... I forgot to include that