When should I seek medical attention for sharp pain under my armpit?

It's important to see a doctor when sharp pain under your armpit does not go away or if you notice extra signs. For example, if the pain begins suddenly and stays strong, or if you see new lumps, swelling, or red patches near your armpit, it might mean something more serious is happening. Sharp pain that also comes with fever, weakness, or numbness could be a signal that the nerves or lymph nodes are under stress. In some cases, pain like this has been linked to nerve issues or even early signs of tumors near the upper chest, so catching it early is key. If you see tender nodules or if the pain interferes with your everyday activities—like moving your arm easily—it is best to have a healthcare provider look at it. Before your appointment, you can check your symptoms to help identify possible causes and better communicate your concerns to your doctor. They may do tests to see if it's an infection, inflammation, or another condition that needs treatment when pain doesn't let you go about your day normally.