I had an episode of severe leg pain (in my good right leg) that was mostly in the quads this summer. I might have over-extended that leg the previous day, but I couldn't remember exactly what triggered it.

We fired up the generator and I used a heating pad on it which really didn't work.
And by coincidence I had some heartburn so I took my Maalox tablets, and voila...it was gone within a day. Then I realized I wasn't eating the same foods as I do at home-- and my calcium levels might have dropped because of that. So now I am taking the Maalox every day, and that shooting pain in my quads is totally gone.

So you might want to look at your food intake and see if you are not getting enough calcium, especially if you are taking magnesium supplements. I like the Maalox...it is 1000mg per tablet, in quick dissolve form. Its called Maalox ultimate now (it has had 3 names over the years!)