R.I.P. , Chiko

Today is a very very very very very sad day for me. My pet chipmunk died. When I came home this morning, I saw him being very weak. I don't know what to do. His breathing was fast, like he was in pain. He was limping as he moved from one corner to the other. He couldn't balance himself on his left leg behind. I wish I had known what was wrong with him. Even when he tried to climb on his wheel, he seems to not have the energy to pull himself up. And when he tried to run on his wheel, he kept slipping off his left leg. When he climbed around in his cage, he couldn't hang himself up there for long. A few times he tried doing it, but he kept falling. When I caress him, he kept quiet. But when I moved my hand towards his left leg at the back, he quickly tried to move away, though he can't move quick enough. It pains me seeing him like that. But I seriously don't know what to do. I tried feeding him food and water but he didn't want any. I called a few Animal Clinics but most of them told me they don't treat chipmunks. One of them even asked me to go to the Zoo. I feel so helpless. I wished I knew what to do. I wished I knew what happened to him. All I could do was watch him helplessly, seeing him breathing as if trying to hold back the pain. The next thing I knew, he stopped breathing. I touched him lightly just to be sure. He didn't move. I tried picking him up by his tail. He was very stiff. Not breathing. Not moving. He died in pain. I still can't accept that he's gone. Looking at his lifeless body makes me breakdown and cry. But there's nothing I could do now except to give him a proper burial. I know this sounds so stupid... But if only he could talk, he could at least told me what was wrong, and I could probably fix it. But of course, he can't. He's not a human being. He's an animal and animals don't talk. I can't believe he's already gone.... :'(