Oh yeah, one more thing. You may have had a reaction to the Natural Calm because it is magnesium citrate. If you can get your ND to test it on you to see if you have an intolerance to it. I myself have to get tested for every new supplement because I too have certain reactions. This is what happens when we have AF, we become allergic to certain foods, supplements and inhalants.
You can try magnesium glycinate, it may not give you a reaction. I am on my way today to talk to my ND about magnesium as I am having trouble sleeping and having major muscles twitches, both possible signs of magnesium deficiency, which gets heavily depleted when under stress and anxiety.