Is there a way you could set up minimal payments like £10 a month? I know it's not a lot but it's still something. That's what I'm having to do with a £600 water bill.
Is there a service like citizens advice that could be a middle man who could help you potentially set this up? I'm sorry I'm not more helpful, I myself tend to be crippled by the pressure of debt hanging over my head. It's hard for anyone, but more so when you have other things going on too.
And I hope you find the money to see your T when he has a slot available.

and your physical, I hope that goes well.

xx