Thanks for all the advice!
I tried the cold tea and it helped, at the moment I am very broke so can't afford a lot of creams etc.
It is clearing up wonderfully though and is certainly not as bad as the last time I had it (when I brushed past some Giant Hogweed, and my sking actually started to bubble, very nasty).
I am pretty sure that it was caused by industrial strength washing powder on the sheets as it was only on my forearms, the rest of me having been covered by pajamas/socks or my hair. If it was a reaction to my only other known allergen it would probably have been all over my body.
I'll definatly keep the reccomendations in mind for next time!