Hi! These Last Few Days, I've Felt A Tightness In

Hi! These last few days, I've felt a tightness in my chest (it's not unbearable), and I seem to be a bit short on breath. I can feel my heart - almost like a heartburn but not the same. It's almost a bit tingly, like it's fluttering a bit. Since it's to do with my heart, I want to get it checked out. Or at least know what could be contributing to it.
I work out regularly but have thrown in more cardio-based workouts as of lately. Is my heart irritated?