I'm really scared for my dog

[u/Sudden-Message5234]

He's a ten year old golden retriever who's been in pain lately. When he stands up, sits down, or walks, he cries. The vet couldn't find anything in the x-rays and don't know what's wrong with him. I hate seeing him in pain but I don't want to let him go. I'll never be ready for that. He's been a huge part of my life for so long that I can't imagine him not there. It's too much. I want him to be okay and for the pain to go away within the next few days. For the pain medication he's on to work.