Hey there! I think if you are taking the D at night it could cause insomnia. And yes take it with food otherwise I get the worst stomach ache. I take it at lunch since that is my biggest meal of the day, D3 5000IU. I got the prescription for D2 from the doc but I don't think that one is as beneficial. But I agree it definitely gives me more energy as well! Which is a relief. I also have the off/out of balance feeling 24/7 like something is just not right! I'm sorry I can't answer your questions...

Anyway I hope you continue to benefit from your D and calcium!!!