Oh, goodness, ! First off, I am so sorry you experienced this. Second, I am not aware of any members of this community having a similar experience, but that doesn't mean someone here hasn't gone through this.
That said, I assume the ER staff told you that this can sometimes happen with a chemically induced stress test. I do have questions about why you had a stress test and if you were properly monitored during the test, but you do not have to answer those questions, if you prefer not to.
I don't know the exact numbers of how often a response like yours occur, but it's definitely not unheard of.
How are you feeling now? Is your heartrate returning to your normal? Will you be following up with your physician this week or next week?
Best, Erin, Team Member.