It's best to follow the Doctor's advise. Your
Vitamin D levels are very Low so please get the injection. For maintenance of good vit D level one injection is not enough. You need to expose your self to sunshine daily. Also eat vit D rich diet.
Next Steps
You can consult with me regarding a diet for you rich with vit D rich foods.
Health Tips
Daily exposure to sunshine is helpful in making vit D in the body.