I recall my most troublesome symptoms were a rapid pulse, chronic heartburn,
headaches, muscle
and joint pain (especially hips/back)
and feeling so very very tired all the time. I also had 7 kidney stones in two years and, just before I had surgery, my gut hurt constantly and I was urinating about every 30 mins 24 hrs a day.
Hypercalcemia affects people differently and some can be super sick at barely elevated levels, whereas some can seem to tolerate much higher.