Hi and thank you so much for this query. From the information you have provided, I am concerned that you may actually be having an infection of the arm secondary to this injection. Germs that commonly cause this infection are not very sensitive to amoxicillin and you may need another drug to adequately address the germ that causes abscess(staphylococcus). Also, please get this arm examined. it may need beyond simple medication to a minor surgical procedure like incision and drainage of any abscess that might have collected. So getting consulted by your physician is of prime importance. There is no point in being scared of the ER. it is made for sick persons and as long as you are sick, please feel free to visit it. What is more concerning is you not getting the care you need rather than abstaining from the ER. I hope this helps and provides guidance on the way forward. Please get consulted. In addition, you may try some cold packs and pains medications while you navigate your way to the hospital. Thanks and feel free to return to us with more questions if nedd be. Dr. Ditah, MD.