What Causes Low Calcium Levels?

howdy-my HMO Dr. ran a blood test....a wk.later his nurse calls saying everything is normal. i got a copy of the results & found my free testosterone level is 13.4 !! over the years, my calcium has been leaching out. my teeth are all gone,osteoporosis is in play & in 2011(@ age 57) a bone density scan showed the age equivalent of a 72 yr. old....whenever i d ask him where s the calcium going? he d sidestep/change the subject.My A1c level was at 5.6 2 yrs. ago....people haqve been asking me if i m diabetic, cuz i m so thin. on the recent blood test, he didn t ck. my WBC or RED CELLS. His trainee drew 4 vials,yet the test results state the reason for not doing a COMPLETE lab is No suitable specimen received ....what do you think of this??