No, don't recheck. It's a wastage of money.
In AS you get unexpected grades.
I got a B in Accounting AS although I was definite of getting an A, also my teacher would always say how good I'm in Accounting. So I rechecked and the results was the same.
I've got of my friends who faced the same issue, but I have heard of others who got their grades changed.
I say you better concentrate on your A2.