25 y/o f, low testosterone, <20. Can vitamin d help raise testosterone naturally? I can't see the gp for more treatment ideas until 1/31.

No. To the best of my knowledge, vitamin d supplementation will not raise testosterone levels. Low testosterone is not an emergency type problem. You will be ok. Take a deep breath, relax, and see your doctor to discuss it next week.
No re:Vitamin D. Vitamin d will not raise testosterone, and low testosterone is not a disorder in women.