I have been there too. I was climbing up a fairly steep trail with a switchback, started to fall over and unclipped my foot ( the wrong foot as it was on the outside of the switch back) and tumble backwards down the cliff/embankment about 20-30 feet with my bike as my other foot was still clipped in.

My adivce would be to practice those areas. I still get nervous with tight turns but continue to practice my "weak" areas. Just as long as you are still having fun don't worry and enjoy yourself.