Small, hard lump in chest that hurts when i put pressure on it?

As above : Correct diagnoses can't be made without proper assessment . See u pcp for evaluation.

See your doctor: Probably abscess but could be anything. Your family doctor may be able to excise it in his office. If it is fixed-unable to move easily or, getting bigger, you should seek help sooner. Vascular lesions are also very worry some. A mobile lump could be a fatty deposit but these are not painful. See your doctor for this. Finally, how long have you had this, the longer and stable the less worry.