Hi doctor,I am 28 year old ,and i have severe lower back pains and neck pain ,sometimes fatigue,doctor has taken D3 test and found its less than 4,also vitamin B12 is very low around 199, they have prescribed Bio D3 plus for 3 months(one tablet everyday) and rocaltrol and altraday for 3 months (one tablet everyday), is this right ot take this medicines for this much long period?