Francesca, you need to remember that MTB is for fun, not to go and do stuff that's too scary too soon! Be absolutely certain that there is no shame in walking a piece of trail that you consider too sketchy. Go and enjoy the blue, and if there's a skills park go and play at some little drops or berms or whatever.
Alun fell off some wet northshore, and there ain't none on the blue run.
Give it 'til the spring/ summer getting your fitness and smiles up on the blues, then go and push your boundaries on easy reds like Llandegla and Sherwood Pines, and a red/blue mix at Dalby or wherever. Build up to it and you'll love it. Push it too much and hurt yourself and you'll wish you hadn't bothered. Take it your pace, not anyone else's.