Whose Fault Is This, Anyway?

I have a brain. There's nothing strange about that. Everyone has a brain. But my brain is different. It's restless, and its thoughts are extremely active. Especially at night, it's like it's had a shot of adrenaline. It just can't stop. But one day, it started bleeding, and I collapsed on the floor and was taken to the hospital. So my brain demanded to know why I had done this to it, leaving it unable to move at all. I put on a serious face and said, "You can't blame me. There are too many things in this world that make your head hurt." Then my brain locked me up and forced me to find the real culprit. At the very least, I had to answer one question: Whose fault was this? T_T But I can't be stuck here. I still have so much to take care of. The case files at the detective agency are still lying on the floor, I haven't finished my romance game, and most importantly, I think I forgot to feed batteries to my robot cat... So could everyone please help me out? Bookmark my story so I can find the culprit behind what happened to my brain as soon as possible. Theme: Maybe you can't blame yourself for everything.