The feeling of pain during vaccination may be influenced by a variety of factors such as one’s own sensitivity and mental state. The pain perception of vaccination can vary from person to person, and it is impossible to determine what level of pain it is. Most people consider vaccination as mild pain, i.e. grade 1-3, but for a small percentage of people who get dizzy and have a low pain threshold, they may consider vaccination as moderate pain, i.e. grade 4-6. The main clinically applied pain grading methods are digital pain grading and visual analog grading, both on a scale of 0-10, increasing from no pain, moderate pain to severe pain. The grading is mainly measured by the person who feels pain independently, and there are also differences in injection techniques and drug quality that produce pain, so there are large individual differences. If the vaccinator is nervous during the vaccination, the muscles at the injection site may be tense, resulting in increased pain, and excessive tension may make the body more sensitive and the pain more pronounced, and even dizziness may occur. The vaccine should be administered with a relaxed mood to relieve tension, and the injection process will soon be over. If there is still pain after the injection, it may be a common adverse reaction to the vaccination and can mostly be relieved by itself. Sometimes it may also be accompanied by redness, swelling and hard nodules at the injection site, which will generally subside on their own. It is not recommended to take painkillers on your own to avoid masking other symptoms or affecting the immune response. In the short term, pay attention to keeping the vaccination site clean and dry, avoiding frequent rubbing with foreign bodies, and taking proper rest and not lifting heavy objects with the affected arm. If there is obvious discomfort that cannot be relieved, seek medical treatment promptly.