I have fluid behind the eardrum its so painful how can i get some relieve ?

See physician,: I'll give some over the counter measures that might help but if the pain persists please see your physician or an ENT specialist. Fluid behind the ear, serous otitis, can not only cause pain and infection but if prolonged it may cause hearing loss. At home try warm moist compresses as often as needed, Sudafed or other decongestant and Advil, Naprosyn or Tylenol (acetaminophen) for the pain. Good luck.