Acid Reflex or Heart Attack Symptoms

Before the post, some information on me: I'm a 21 year old, 5'7 male, 120lbs. I live in Canada and take no medication with no existing medical conditions.

So, a few weeks back I started to have some pretty annoying chest pain/discomfort and after a few days of dealing with it I finally did went to the doctor to get it checked out. I ended up getting an xray, some blood tests, all the tests they'd do when you go in for chest pain.

They sent me home saying it was simply acid reflex and that I should be fine. But it's been probably close to two weeks since I've been there, 3-4weeks in total since this started (There was a brief period of 3-5 days where there was no pain/discomfort).

Although the things im experiencing are potential heart attack symptoms too. Chest pain, discomfort and it gets a little bit harder to breathe occasionally. My dad has acid reflex issues and has NEVER described it like this.

I'm getting nervous again at this point, but the doctors did go through pretty much everything they'd need to I assume. When I left, they told me I was a healthy/skinny male and I should be fine. What are the chances they're wrong? I really don't want to go in and spend 3-10 hours at the hospital again (Hospital waits can get pretty long here) to be told im fine and just have acid reflex.

Any advice is greatly appreciated, my nerves are really getting to me at this point.