I had a similar issue. I had strong chest pains and thought it was a heart attack, but waited a day to be seen. They didn't give me any heart drugs that I remember but they ran tests, took images, etc.

Turns out it was a severe anxiety attack. Been getting them ever since, but not every day, except this last week. *sigh* The ER doctor said as long as the pains don't bring a feeling of weakness it isn't likely a real heart attack.

I am not a doctor and that is not medical advice and I can't say you are having anxiety issues. What has been working for me lately, besides all the the meds, are lavender candles.

I am very sorry about your grandma, I lost mine a few years ago. It is a tough thing to handle.