Arm very red; Arm bruised; arm was very sore; Injected in an improper location; he felt pain with the needle and pain while the liquid of the vaccine was entering to the arm; Arm  immediately started to swell up; A spontaneous report was received from a consumer concerning a male patient, of unknown age, who experienced feeling pain with the needle, pain while the liquid of the vaccine was entering to the arm and arm very sore/MedDRA PT: vaccination site pain, arm immediately started to swell up/ MedDRA PT: vaccination site swelling, arm very red/ MedDRA PT: vaccination site erythema, arm bruised/ MedDRA PT: vaccination site bruising, and injected in an improper location/ MedDRA PT: product administered at inappropriate site.  The patient's medical history included recurrent kidney stones, allergy to penicillin, and drug allergy to rovastatin.  No relevant concomitant medications were reported.  The patient received his first of two planned doses of mRNA-1273 (Lot 011L20A) on 08 Jan 2021 intramuscularly in the left upper arm. On 05 Feb 2021, prior to the onset of the events, the patient received his second of two planned doses of mRNA-1273 (Lot number: 031L20A) intramuscularly in the left upper arm for prophylaxis of Covid-19 infection.   The patient stated that when he received the first vaccine on 08 Jan 2021, it was a wonderful experience, and he did not feel the injection and did not experience any side effect. But, when he received the second dose on 05 Feb 2021, the injection itself was not well administered. Injector was distracted or not fully trained, and the patient felt pain with the needle and pain while the liquid of the vaccine was entering to the arm. After that, injector put a bandage but caller states that it was not placed where he receives the vaccine. While he was leaving the facility, the arm immediately started to swell up. The patient stated that he thought the swelling was due to accumulation of the vaccine in the place where the vaccine was really administered, a few inches away from the site the first vaccine was administered. The day after the arm was very sore, red and bruised, but he thought it is because the administration of the needle, not a side effect of the vaccine. Both vaccines where administered in the upper left arm, but caller does not known if the second was in target. Unfortunately, had an incompetent injector who gave him a painful experience with the injection and the realize of the vaccine. Wanted to find out if should be concern that may have injected in an improper location and weather if gave him in other location, if should be concern that he may have not full effect of the vaccine.   Treatment information was not provided.  The patient received both scheduled doses of mRNA-1273 prior to the events; therefore, action taken with the drug in response to the events is not applicable.  The outcome for the events of feeling pain with the needle, pain while the liquid of the vaccine was entering to the arm and arm very sore, arm immediately started to swell up, arm very red, arm bruised, was unknown. The event, injected in an improper location, was considered recovered.; Reporter's Comments: Based on the current available information and temporal association between the use of the product and the start date of the event a casual relationship cannot be excluded.