I left England after my GCSE's but from friends I understand the jump in difficulty from GCSE's to A-levels (or AS or whatever they're called now) is pretty steep. I don't want to rain on your parade, but do you feel you could realistically achieve A's and B's in A-levels after not getting one A in GCSE's? Because frankly, for the people who you're going to have to compete with, GCSE's were a joke, and most get straight A's in their sleep. Are there other extenuating circumstances that prevented you from doing better? Sometimes the most intelligent people slack and say they'll turn it on once it counts, but most don't, mostly due to lack of discipline, something that can't just be turned on overnight. I have a few friends who graduated from UK med schools that I've spoken to, and they say yes, you could get into a UK school if you ace your A-levels, but I'm sure some of them would still want to know why you did poorly in your GCSE's. You're going to find the work much more difficult, especially with the A-levels you've chosen. A counsellor to help you with study skills and time management might be helpful