Sounds very much an anxiety situation, I had a heart attack 3 months ago and trust me, it's a very different experience to what you describe, even the warning signs. Start worrying when you end up on the floor in a cold sweat losing control of ALL your bodily functions whilst in extreme pain.
I'm not saying what you're experiencing isn't scary but it's highly unlikely you've got a cardiac issue, it's almost a good sign you feel your heart racing in that respect.

Definitely and MS downfall . i never experienced that at first but now its out of control and was told it's anxiety .

Do you get heart plapatations or fast heart beat? Xx

I had a small episode on Tuesday morning, my heart was pounding really fast I would done my breathing exercises, once it calmed down I was then sick.. it was just random.. but getting bloods done along with ecg in the next 2 week's x havent experienced anything like this before, and thank you for responding.. Hope you don't experience to many heart plapatations

Palpitations & asma....yes. use a brown inhaler twice a day, pernicious animia-palutations...Yep. x