Does Vit D CAUSE PAIN

HI!  I was dx'd last summer(2010) w/ a vit d def., by my cardiologist. My level was 20. I had been exhausted for 2 yrs prior, & felt broken from the waist down. It felt like the muscles were being ripped off my hips, and my lower back was killing me & hips were on fire. Noone found the problem, until I went to the Cardio for tachycardia and palpitations.(Thank God I went to the cardio dr) anyway, I took the labwork to my new GP & he put me on 50k a wk for 8 wks, w/ follow up bloodwork to be done at 8 wks. After the 2 nd week, I was in excruciating pain, worse than when I started. Is that normal??? I also got very constipated. I was'nt sure if from lortab (for pain) or from the vuit d, but think that I had a small obstruction. It resolved itself, but I thought I was going to die. I went back to my gp, & he did not want to run another vit d test, so I stopped it b/c if noone is going to monitor it, what the heck is the point? Anyway, I decided to take 400 ius daily (started 3 months ago) started to finally feel a little better, but then got tired again, and pain came back, not terrible, but uncomfortable. Anyway, I started back on vit d. I got the liquid, 1k per drop. The 1st night, I did 2k, the 2nd night, 3k...by the 4th night & 5th night, I took 5k ius both nights. The pain became excruciating again. My hips & back & could barley walk. I heard on some sites this is normal, as it is the calcium going back into the bones, but my goodness, I can barley move & the lortab barely touches the pain. If anyone else experienced pain increase after being on vit d, please let me know. I don't know what to do, afraid if I don't take it, I will be exhausted, w/ weak muscles, but if I do take it, I will be in severe pain, & it takes months to go away. I have started this 10 months ago, I can't live on lortab. This is crazy. I am worried as to what is causing the vit d deficiency to start w/. My cardio said my para-thyroid was normal,I am worried about my kidneys being the problem. Also, I noticed I pee a lot on the vit d, and am very, very thirsty, which thirst & frequent urination go hand in hand. Thank you for reading this. I am worried about the pain, I also work, so this is getting to be a big problem, & I can't take the pain that I am getting after taking the vit. D.