Over the left side of my chest where my heart is , i feel like it's been twitching, only in the area, what could it be?

Superficial twitch?: The left side of the chest also holds many muscles both superficially and deep within the chest wall. Twitching is usually a specific sign of muscular contractions (twitch, i.e. Fasciculations). This is usually not related to the heart. The equivalent of muscle twitch for the heart would be the sensation of premature beats ('skipped beats' or 'palpitations'). Sounds like you have a muscle twitch.