Only 16..?

My whole life I have noticed a few odd problems from time to time. Next to that, well receiving medical training (through a program- because I am interested in that for the future.) I was told by the certified nurse that I should seek and look into a pace maker or A1c.

She told me this because very randomly I get the most discombobulating dizziness- very quickly comes on for almost no reason seemingly. Next to just that... I have never been able to take hot showers because I WILL pass out. And on only 2 occasions I have passed out immediately after a sporting event. (I am fairly active and run a 1-3 miles daily and participate in track at my school.) I also tend to experience breathlessness when I am laying down and I feel like my heart is in my brain during that.

No one in my family is listening to this, and I just wanted to make sure that these issues CAN wait to be looked into or if I should be extremely urgent with these thing, and what may be happening to me. Please help...

Hi,

This is something you should try to get checked immediately. I have been to 3 cardiologists In the last 4 months. Thankfully, they say nothing is wrong but they said that undiagnosed heart conditions are the #1 cause of death In teenage athletes. 

Do you have an abnormal heart rhythm or any history of heart disease in your family? 

At times I feel as though my heart skips, or stops or speeds up. But no heart problems in the family.