When I had my heart attack, it felt like my heart just hardened and I had tingling/numbness from my middle back to my left fingertips.
The two days before my MI, my body was stiffening. Probably because the blood flow had almost stopped and also, couldn't breath.
If you feel major back pain or your heart hardening, you will know that it's a heart attack. I would go to the ER anyway and demand an ECG.
I have that sensation for a bit while. I also told it is the reflux/heart burn. I took Nexium 40mg and Tazac 150mg twice a day. These doesn't work at all.
Mine one keeps come and go, it can stay in a whole day! I felt my heart is not beating too. It is real, when I had a 24 hours holter monitor, it said my heart "Pause" 3.2 second in the afternoon. My cardio said it is "anxiety"! Nothing to be worried about.
Later on, now what I have. I'm like living inside the space ship. Whole day I full of light-headed, tightness, SOB, nausea, seeing stars, stomach ache and dizziness. When I lay down on the bed, it spins. Can you immagine how I drive? Well, anxiety and reflux can drive a car, isn't it?
We are in the same boat, aren't we? Please keep me updating if you find out how to cure that. Take care.