How do you accidently check yourself into a mental hospital?

I was pagbaba a Diary I kept when I was thirteen, I had mentioned my current paborito telebisyon character (Robert Goren from Law & Order: Criminal Intent) and then I sinabi he'd accidently checked himself into a mental hospital, my first response was knowing the character that he'd probably done it on purpose but then I was wondering what exactly thirteen taon old me meant and I started trying to figure out how it is possible to accidently check yourself into a mental hospital. I still haven't, you tell me if it's possible and if so how?