White Crusty Bumps on Feet and Ankles

You need to see a dermatologist before it gets worse.

Ditto on seeing a dermatologist or your doctor. It sounds like it might eczema or psoriasis and are easily treatable.

Too much calcium in the system.

Just want to add that too much calcium causes internal organ problems so it's highly unlikely that's the cause of your skin rash which is an external organ. See your doctor and let a professional explain what the rash is and what the cause of your rash is from.