I知 freaking out! Earlier today I coughed and next thing I know, I have these flashing lights ALL over my vision. It went away after about 5 seconds. I was just watching the news about a 30 year old who had a massive heart attack, and she saw flashing lights in her vision right before it happened. Now I知 terrified that I知 about to drop dead from a heart attack! Is this a heart symptom?! Please help!