Hi Doctor. I Started Having Leg Cramps, Weakness In Legs,

Hi Doctor. I started having leg cramps, weakness in legs, and tiredness. Went to GP, got all bloods done, all normal but came back low vit d, reading was 13. I received vit d injection as Gp said I needed a boost first and has put me on Desunin D3 800iu/day for 3 months. Nearly 8 weeks down the line my cramps etc have improved in legs but soon after starting treatment I experienced bad bone aches alternating from hips to thighs, and now in lower back-i had none of these beforehand. So just want to know is this normal? is it the bones mending themselves? Do you get worse before getting better. Have improved my diet and exercise still feeling very tired. Have to go back to Gp in 6 weeks when she will recheck my levels. Should I get magnesium or iron checked too, though I think she said iron level was okay. Thanks Doctor.