I was told i have costochondrotis and chest x-ray and ekg are normal. how soon will i feel better? can sitting or laying certain ways cause this?

Costochondritis: Is due to inflammation of the costo-chondral junction where ribs join with cartilage in the anterior chest wall. It can be brought on by physical exertion, stressing the chest wall or by minor trauma to the area; less so by lying in particular positions. Treatment is typically by use of nsaid's and by not restressing or reinjuring the tender area. It typically resolves within a few days.