If you follow a vegan diet, B12 is not found naturally in fruit, vegetables or grains, so fortified foods or a supplement matter more, and seaweed, spirulina and similar products are not reliable sources
Clean the injection site gently with alcohol swab to avoid any kind of infection
With intramuscular administration, creatinine levels may increase, this should be considered when making a diagnosis
However, that does not mean you should not, at the very least, not with the permission or direction of a physician or other health professional
CPT 99211 is a nurse-level E/M code that implies the physician was not present during the encounter