I have this random chest pain that will come and go every now and then. it happens after being a bit down, but it tends to be extremely painful. wory?

Need H&P: The etiology of the chest pain is very broad. Given that it is associated with mood makes me concerned about a psychosomatic pathology or an anxiety/panic disorder. That said, these are diagnoses of exclusion because your physician will likely want to make sure your heart is not the problem by doing a history, physical & poss tests. Another common etiology would be musculoskeletal dz. See your pcp.

Probably not: At 21, random chest pain is likely musculoskeletal. Mention it to your primary physician, and hopefully you will be able to be reassured.