[rayalez]

It's anecdotal, but D3 actually messes up my sleep and leads to the symptoms you're describing. I've read similar reports on reddit and forums.

Try to lay off D3, and try to take more magnesium citrate separately, this helped me.

Apparently, half-life of D3 is about 3 weeks, so if you've been taking it for awhile, you can have a lot of it in your body all the time. I'm not a scientist, but my best guess is that since D3 is meant to be released under sunlight, too much of it could be doing something to interfere with your sleep.

Again, just a layman's guess, but true in my personal experience.