hi there poppy.
Right wel if you put Colchester into the search machine you 'should' find some Colchester names. Pm them and ask nicely if you could have a wee try as you are not sure if its adults or kids 4 u.
Now 4'9'' really does put you in the kids bracket Id say. But as you are getting them for christmas you dont need to order till mid of December --or later ( picture webmaster tearing hair out screaming ---no order early christmas is a nitemare) and you may have gained a lil.
However, your twisted spine ( sorry to here) complicates things a lil. Does this make you a bit shorter? Cos when we talk about height we do so cos it is indicative of leg length ( do you see). Thats why it really would be good for you to get a pair of adults to see ( and if you could take a couple of foam blocks along to puton foot plates all the better).
last thing, when is your birthday?
Thats as bst as I can advice