I got woke up at 2 a.m from a really bad pain under my left breast. every time i try to take a deep breath it hurts worse! do u have any suggestions ?

Call 911: The tightness, pain or pressure under my left breast is always a red flag and visit to the ER or Urgent Care is warranted. Do not drive, call 911.

Pleuritic or muscle: This kind of pain can come from spasm of the muscles between your ribs or from the lining inside your rib cage called the pleura. Much less likely is something growing into or around the nerve on the rib. Persistent pain is likely from inflammation of the pleura like with a cold. Treat the cold plus pain med. If muscle spam, stretch your side. If persists 24 hr see your MD. Chest expansion = pain.