Squash is brilliant. Used to play a lot when I was at school(at a very high level I might add) but fitness more than anything else can win you a squash match. Keep playing it, squash is a sport that is beginning to die out (especially at a junior level) and it needs all the players it can get to keep it going.
FWIW, a man called Alan Clyne is Scotland's best squash player at the moment, currently ranked somewhere in the top 50 in the world.