I did a flu vaccine and i can't sleep because the arm is sore. what should i do?

Tylenol, (acetaminophen) ice: Take an over-the-counter pain reliever like tylenol (acetaminophen) and right before going to bed apply ice wrapped in a towel on your arm (a bag of frozen peas works well) for about 10 minutes. The pain shouldn't last more than a day or two.

Sore arm: Soreness is not uncommon from any vaccine. You may use advil ( ibuprofen) for the discomfort. Sometimes warm soaks will help as well.