Could it be possible that taking vitamin D (1000 IU/day prescribed by my doctor) is causing me diffuse muscle pains?

It is unlikely that taking vitamin D would cause muscle pain. However, if you suspect that it may be causing your symptoms, you could try stopping it for a few days to see if the pain improves. If the pain returns when you resume taking the vitamin D, you may want to speak to your pharmacist about alternative options. Additionally, the atorvastatin medication in your medical history could potentially be causing muscle pain as a side effect. It might be worth discussing with your healthcare provider about adjusting the dosage or switching to a different medication in the same drug class that may be better tolerated by your body. I hope this information helps address your concerns.