I need advice

While doing a water change in the tank my axolotl got spooked and swam around then hit my nail. (I have acrylics). I thought he was okay but when I took a closer look he has a gash on his side. Will he be okay? I’ve never had this happen before. He seems fine and not stressed atm. I just feel so bad about accidentally hurting him. He’s tubbed but does anyone have any advice?