Hello,
I had gone through your question thoroughly.
I would like to tell you that vitamin D of 24 is not that much low which requires supplements. If the level goes below 12, then usually it requires vitamin D supplements. Vitamin D deficiency will not lead to tiredness or anything like that. It mostly leads to osteomalacia, means softening of bones and more prone to fracture even after trivial trauma.

So i would recommend you to take vitamin D rich food mainly milk and milk products, also go for sun bath before 10 am for atleast 30minutes daily, reduce your weight if its on the higher side. Pulse rate of 76 is absolutely normal, it can be anything in between 60 to 90, so don't worry about it.

So just relax, you are absolutely normal and enjoy your life and remain stress free. Hope this will help you and let me know directly if you have any further related queries.

Welcome!
Your case is complicated and a generic answer telling you how long it will be before you feel better is not fair to you. Your case is complicated by receiving Sandostatin which tends to cause vitamin D deficiency in 18% of Federal Drug Administration (FDA) Reports on Sandostatin side-effects. It appears that dosage adjustment might be tricky and more frequent testing with Vitamin D3 dose adjustment may be required to get your D in the optimal range.

Low levels of vitamin D can affect calcium balance, so you may wish to talk with your doctor about this as well.

Further information on this subject can be found on the FDA site.
Best of luck to you!

Regards, Kathryn J. Shattler, MS, RDN