How to get through this

My father (age 53) had a heart attack today. I feel awful even saying the word heart attack. He suddenly got up in the middle of the night with similar symptoms to indigestion. Me and my mother were asleep and couldn't get a proper assessment of his situation. My aunt lives with us and she immediately rushed him to the hospital since my mom can't drive. Right both my mom and my aunt as well as two uncles (one from mom's side and one from dad's side) are at hospital with him.

Everything happened so fast, they immediately put a stent and are monitoring him right now. He was in so much pain. I feel awful because I was tired and didn't get up to see him. He gets indigestion occasionally so I thought it was that. I feel so much guilt as well as a sense of disbelief. I had known next to nothing about heart attacks a dozen or so hours ago and now I'm panicking.

The thing is that I don't have any friends or relatives to ask for information. Like I said I don't know much about heart attacks. I don't know how recovery works nor do I know anything about treatment. The only thing I feel is just this horrible feeling sense of my world turning upside. I'm just in disbelief and can't pull myself together but I want to know what I can do from here on. I am also unsure on how to provide support for him since I feel like I'm not calm nor mature enough for that right.