#1) You basically want to see if some of your bones are painful when pressed

Press with about 10 lbs (4 kg) of force at the bottom of your sternum and your tibia

#2) German website asks a few questions about how you feel

The deficiency of vitamin D can easily be diagnosed by the signs Acute Vitamin D deficiency Syndrome (AVDDS) (Brugge- 2009)

The computerized test asks about frequency of the following:

My fingernails have small white spots, dots or cross lines ... Weakness, Sadness, Listlessness, Tiredness, Muscle-Pain, Eyelid twitching, Arm twitching, Legs twitching Cramps, Cramps at Night, Circulation problems, Dizzy - standing up, Dizzyness on Exercise, Dizziness that disappears when lie down Headache, Headache - Standing up, Headache - Sport, Headache it disappears, when I lie down ... Standing causes backpain, Standing causes hip-pain, Standing causes groin-pain, Standing causes leg-pain. Standing for a long time I feel pain of my legs ...

These tests probably only detect levels of vitamin less than about 20ng/ml

More details and more type described HERE