Bear in mind that Economics A-level is nothing like Economics at university, there's almost as much (maybe even more) Math in the degree as there is in the Comp Sci degree! I'm leaning more towards Economics instead of Electrical Engineering/Comp Sci, though if I get into an American university I'll do both.
Are you still trying for internships next year? If you are, could you please PM/Facebook me about them. I assume you are not applying for the 6 week residential Wharton summer program, are you?