I have gone through 2 heart attacks and the first one was painfull not sure if it felt like a bullet as i have never been shot in my heart but it was bad. I had severe sharp pain in my chest the radiated to my arm and shoulder and couldnt breathe. My second more severe heartattack I was walking in the park and didnt even know it till i went into my drs appoint that day and had my ekg done but they say becouse im diabetic my pain sensors are working so well so it wasnt as bad .I guess it hits people different depending on circumstances.