Peterspots-
you never told us your actual level of Vit d measured in the blood. A daily dose of 3000 will raise your blood level, after about 3 months, by roughly 75 nmol/L if you are an <span class="underline">average</span> person . However , the response is variable , up to six times variability, depending upon your genetic heritage etc.
Also people with greater body mass will respond less, lower body mass will respond more. That is why it is really important to actually measure what your level becomes after several months. It takes around 3 months or more to rise to a constant level when you take daily supplements.
Try to ensure your blood level rises to at least the minimum of 75-80 nmol/l as recommended by the American Assoc. of Endocrinologists for bone health. Make sure you have a daily intake , not weekly or longer intervals . make sure the supplement is in D3 form , cholecalciferol(i.e. mammalian form ) and not D2, ergocalciferol (i.e. the plant based form)
As you may see from my previous posts, a blood level of 120 -140 is most likely to be better for you, as that is the blood level we existed with , over millions of years , as primates. It is only when we migrated to Northern Latitudes, covered ourselves in clothes, then latterly suncream , etc, being afraid of sunlight , that we became deficient in Vitamin D.
IF your low vitamin D is causing your problems , then please realise that it will take months for your body to put right problems that have been developing over months and years. You must ensure you have a healthy diet , with all nutrients, including calcium and all the other vitamins and minerals and protein from meat/fish etc etc. Vitamin D instructs your cells how to use the nutrients you give them, if you don't consume those essential nutrients, then Vit d cannot help. However without sufficient Vit d , your body will struggle to repair itself, even if you have a "good" diet.
Good luck . Hope this helps.
BTBH