but it occurs to me that your issue is that your objective of speed outdid your abilities in accuracy. My suggestion would be to slow it down enough to have consistent accuracy--and I am an expert on that particular tactic 
--and only when you have the accuracy down that you work on speed. Even then, I would only speed up enough to where you're challenging yourself but remaining largely accurate and consistent. Stay at that speed until you are consistently accurate, then get faster again, and so on. That way, you are staying accurate and truly only challenging yourself on speed, which is your goal. Then practice can make perfect.