I came into the ER on 7/3/2020 due to a cellulitis infection on my foot, as a complication of a bee sting from a week before that. I was given a pill and two shots--one in my hip, and a tetanus shot in my shoulder. The tetanus shot was not to treat the cellulitus; they asked me when I last had a tetanus shot and I didn't remember, so they (hastily) recommended that I get one.  The shot was administered into my left arm, high up near my shoulder. It pinched like any other vaccine, and immediately after was sore which was to be expected? but I also noticed I could not lift or extend my arm too far or at certain angles, because it felt weak and caused pain. My shoulder also hurt.  I expected the pain to disappear or at least lessen within the next few days, but it did not. A week later, it still hurt just as much and I had the same limited mobility, plus general weakness that affected my whole arm (especially while lifting/extending it) and in my fingers.  The new pain and mobility issues in my arm were interfering with daily tasks such as taking a shower (trying to scrub my back hurt), getting dressed, and working at my computer (typing). It got worse at night when I was trying to sleep, and I had pain or discomfort in most sleeping positions but it was worse if I slept on my left side. It also got worse when I moved it too much. Sometimes rest or exercise helped but sometimes it just made it worse.  I should mention that these symptoms are not normal for me, which I found concerning.  About 1.5 weeks after the vaccine, I started experiencing pain in my left hand. I also noticed that after waking up, my left hand would be numb and tingly. Ever since I developed these arm/shoulder symptoms, my left hand was very numb in comparison to my right upon waking up, especially when sleeping on my left side. Like when legs fall asleep, moving my hand around made the numbness go away after a few minutes.  I know that in most cases, pain from vaccines goes away after 2-3 days. So I did some research and my symptoms seem to match something called SIRVA, or Shoulder Injury Related to Vaccine Administration. Symptoms often include arm and shoulder pain, shoulder dysfunction, limited range of motion, tingling or loss of feeling, and weakness. If untreated it can cause issues like frozen shoulder or nerve injury. It?s typically caused by an incorrect method in giving a vaccine, for instance, by putting the needle in too high on the arm or too deep into the muscle.  The pain persisted for about 3 weeks, and gradually lessened. I still could not lift anything heavy, sleep on my left side, or extend my left arm in certain directions without a range of mild discomfort or pain... like when I reach to scratch my back or attempt to put on a tight shirt (getting my arms in requires specific movement). My mobility is still limited, but not quite as much as it was in the first week. My mobility is definitely more limited than it was before I got the vaccine.  I still have these symptoms currently (9/12/20), which have somewhat (but not entirely) lessened with treatment (steroid shot in my shoulder (9/01/2020). I have been seeking testing and treatment with a bone & joint doctor  who confirmed via X-Ray (7/21/2020) and MRI (8/27/20) that I have tendonitis in my shoulder. I started with the X-Rays and returned for an MRI when I saw no improvement in symptoms after following through with ice and exercises, and got the steroid shot during my follow up visit after the MRI.