Sounds like anxiety. Fasting increases your adrenaline, if you’re prone to panic attacks it’ll increase your chance of getting one.
You’re not going to get a heart attack from fasting, and if you had a heart attack you’d be in the hospital. You wouldn’t be asking reddit if you had one.
That’s weird, never had that happen. If fasting makes you feel abormal dont dive right into it.
It would be worth scheduling a yearly physical with your doctor soon just to get bloodwork and have him check your heart etc before embarking on a fasting regimen.
It could have been a fluke and you were just having a bad morning, but only the doc can tell you that for sure.
Same thing happened to me. I was on our 40 of a 72-hour fast and my heart rate started going 130 beats per minute and I felt like I couldn’t breathe. I wasn’t sure what was going on so I broke my fast.