How low is your heart rate? I suggest seeing a doctor to eliminate possibility of low thyroid or infection.
Did you actually faint or just feel like you were going to? Could be simple low bp or simple anemia but it does seem a check up is in order. Without other heart symptoms I suspect it is something outside the heart but best to get checked out by a doctor if this continues. And maybe also post your question in the diagnosed symptoms section to see what others have to offer for fainting spells.
i just felt like i will faint...but didn't...gart rate was normal around 63-65...i felt good when i stopped watching my phone and looked around..
Could be a simple BP issue and likely nothing to worry about but go and get a check up just to be sure.