...I say no.
the reason I say that is that I managed to get an A* in GCSE maths, and ended up getting straight Us for much of my AS course, until I managed to get a grip on some of the material and ended up with a low C.
I resat one module to get a B overall
To do A level maths you need to have a lot of confidence in your ability to understand maths and be prepared to do a hell of a lot of work outside of lessons. At the end of the day, no one online can tell whether you'd be able to cope with the work, but I know I couldn't and I was in a very strong position to do well.
Getting a B at GCSE maths is excellent, and probably meets the requirements of many colleges to study maths at A level, but it doesn't necessarily mean that you will be alright doing the course- my school didn't let anyone who didn't get an A do the course. Do some more research into what the course entails and talk to people who are doing the course at the moment, to get some idea as to how hard it is.
Hope that helped?