ALA did that to me too. I'm not diabetic, but within a few hours of taking it, I felt very weak and shaky all over. Not the weakness in a specific area that my neuropathy causes, but an all over weakness.
I tried taking it in the morning with my smoothie, and it still did the same thing to me.
I bought a glucose monitor, just to be sure, and I was having low blood sugar within a few hours of taking it, which resolved once I stopped the ALA.