Been in hospital with burns - next A2 exam on Monday - what can I do???

I got "severe" sunburn of over 30% of my body, despite applying factor 50 sun cream over all my body (I am extremely pale). This was saturday.

By sunday my legs dhad swollen twice their normal size, and my toes became numb.
So I got rushed t hospital where they took me by ambulance to a specialist burns unit in the north of england.
I was there till very late monday night.

I'm now unable to walk, my legs have severe sunburn, still very very swollen and covered in bright yellow blisters. I'm in agony trying to walk and sleep any everything.~
I've had 2 migraine attacks since and keep throwing up nearly everything I eat.

I'm petrified by the fact I have my A2 Biology exam on Monday and my A2 Chem exam on Wednesday, when I've not been able to revise at ALL in the past 5 days. I know for fact there is no way I am able to get my unviersity grades now.
I've already sat 5 exams, but these last 2 are probably my most imporatnt, but i've been so so ill.

I'm already granted special consideration due to extreme stress/anxiety attacks/weight and hair loss.

Now I feel like this is the last straw. I'm so utterly depressed.

My 6th form are thinking "maybe" if I am unable to sit the 2 exams left that I might be able to get an average grade granted to me...
But what would this involve?
I can't find anywhere on the internet about getting my grades granted without sitting the exam?

Any ideas or advice is really appreciated.

This is the first time i've been able to sit up in bed without a migraine or throwing up, to type this. But I feel incredibly ill.