Ah, that's why I recommend to people that they learn how Vitamin D works. Like so many things, including Iodine I have found, we can be grossly deficient in things, like D. It is not as simple as getting enough sun, especially if levels are diminished to start with. Too much to explain here, but highly recommended for folks to discover symptoms of and then solutions to Vit D deficiency. We were very surprised to not only learn of the many symptoms, but the turnaround in several people, not the least of which was my wife's situation that went on for years, but correcting these levels. Knowing what I know... I'd do it.
Important to know that if D levels are low, it can be difficult to raise the levels back to normal through oral dosing of over the counter D. Just a tuought...