b12 self injection sites How to Give Injections at Home to Yourself · PA Relief Instruction Guide for Intramuscular (IM)
Description
Certain conditions may blunt or impede therapeutic response to cyanocobalamin therapy
However, due to lifestyle factors such as limited sun exposure and dietary insufficiencies, many individuals experience Vitamin D deficiency, which can manifest as fatigue, depression, and weakened immune response

If your B12 deficiency is not diet-related, you'll need to take B12 injections
Other waste (wrappers, swabs) can go in ordinary trash