Both my brothers did A-level economics (I never did) after having only got C's in GCSE maths. They now both study it at Uni, so must have really liked it, and did reasonably well in it. However, they now (particularly the older one who is in 2nd year) are struggling with the maths for degree-level Economics.
In short, you'll be fine, but won't be if you take it any further.