4 days ago (Sun) a mild pain started in my right side under the rib cage and slightly towards my back. It worsened over night and I saw Dr Monday who DX muscle spasm - also gave me a flu shot. Developed a fever w/chills on Tues evening and saw immediat

?Flu vax reaction. The original symptoms may have been muscle inflammation,gall bladder attack or inflammation/infection of the right lung. The fever and chills could have been a reaction to the flu shot but infection in lung or gall bladder must be considered depending on the appearance of other symptoms. Call your physician if symptoms persist or change.