Vitamin D deficiency question

by Neo
(Europe)

First of all I would like to thank you for this possibility to ask my question. There are not many specialists of vitamin d3 deficiency where I live so mostly I gain my knowledge from the internet.

My problem began about 10 years ago. I started to have those weird headaches at the end of my skull and in both temples. Those were rather rare, so I was not paying to much attention to. But each year I was feeling worse and worse. I had no energy to do anything. I was always asleep, kind of depressed. Sport was no fun for me because I didn't see any improvements and it was always terribly exhausting for me. I started having "heavy legs" and lower back pains. Then I started to sleep for 10-12 hours a day.

3 years ago it was a complete disaster for me. I gained all back pain which then expanded to my entire body. Headaches came constant each day 24 hours. My legs, arms and face with neck started to ache and burn. I was feeling so terrible at the age of 25 that I couldn't wake from my bed. There was a time I wanted to die.

I was looking for a right diagnose but I couldn't get any. I was told I am in a deep depression and started taking medications - none of them helped. Then I was considering fibromyalgia.

And finally someone took a test of "tetania" which was positive. My blood results for MG, CA, F and Parathormon were normal. But my D3 level turned out to be 12 ng/ml. I was prescribed 2x1000IU of a drug consisting D3. After one month I couldn't see any improvement. So I started research on my own and found out that those dosages recommended by doctors and health specialists are all bull... and that 2000 IU per day won't even be substantial for my daily needs.
I am now taking around 15-40k IU daily. Depends on a day actually. I also try to get as much sun as I can. But I still have no improvement in my life and health. I read all the other answers here and found out 1 month of supplementation is not enough. So my questions are:

1. Should I remain on 40.000IU per day?
2. When can I expect to get D3 blood level of 75-80ng/ml?
3. When will I finally feel better? I can't wait to it since for last 2,5 year I had no life at all.

Thank you,

Neo