Not sure what i'm feeling with my heart. once in a while when working out, i'll feel a flutter or two in my chest. but maybe it's a palpitation. feels like it beats really hard for a single beat. arrhythmia runs in my family. should i be concerned?

Your description suggests that you may be having premature beats. The symptoms associated with premature beats may be alarming. However, in the presence of an otherwise normal heart, they may not be serious or life threatening. The key is a careful examination followed by Holter monitor to document the arrhythmia if any. An echo will be reassuring if normal. I would urge you to see a cardiologist