AIBU to want a week off work with stress?

[Namechangedtoprotect]

I have no idea how this works, before I have always worked regardless. I feel I can't keep going into the office, it's too much for me. My heart hurts, it hurts to breathe, I've stopped sleeping. Every little task seems to push me over the edge, I feel I'm pushing a rock up the hill and the hill keeps getting steeper. I've spoken to mangers about this and they say there is nothing they can do. Would I be unreasonable to see the doctor today, explain this and hope I get a week off work to recover and get my health back (and also look for a new job). I've started wishing I was probably ill again so I can go to hospital for a break. I think I have lost track of what's normal. I've been at 120% since January and I'm hitting my busy period now.

Well done you, I was in a similar position late last year.
My wonderful GP signed me off for a month, at my back to work meeting I was told I'd not passed my probation (had been officially promoted, despite doing the job for over a year - more fool me). Anyway I was offered a position with no responsibility and on a much smaller team, best move I ever made.
No pressure, no phone constantly ringing, I've got my life back. Only downside is the pay cut, but I'm managing ok, just changed some things in life to reflect this.
Is there any way you could do something similar?
Now I look at the lady doing my old job, and think on you go, pet, it isn't worth it. I might also singer to myself at the mistakes she's making, but hey she looks down her nose at me as I'm not worth speaking to now I'm not management.