I take 4000 iu of vitamin d a day, will i run the risk of hypercalcemia by doing this?

Maybe: It depends on what your vitamin d levels are. If your level is greater than 100 already you may be at risk. If your levels are under 30 you are likely not at risk. However, be aware that active vitamin d acts on a gut receptor increasing the guts ability to absorb calcium and if you are taking large doses of calcium regardless of the vit d level you are at risk. If you have sarcoid avoid vit d.

Probably not, but: Probably not. Generally 2, 000 units of vitamin d3 is adequate to keep levels normal. 4, 000 isn't generally needed, except every other day.