I had issues with heart palpitations for years. Don't have them very often now, but they caused me huge anxiety.
Food certainly affected mine, though other things did as well. After reading a few articles I avoided the obvious things like caffeine, but also fruit juices and bananas and tinned salad beans. I was once a little ill with what was probably a virus, then drank fruit juice, and ended up in A and E with tachycardia and my heart skipping all over the place. The one thing to avoid is energy drinks - caffeine and sugar is a very bad combination for anyone with heart issues. Check the ingredients of your supplements and gels.
https://www.dailymail.co.uk/health/...s-blamed-foods-ripe-bananas-cheese-beans.html
Ecgs are useful, but they are just a snapshot. Likewise, I have had 24hr monitors on a 'quiet day' that only caught a few hundred skipped beats, when other days I have had them all day long.
If you are young, doctors are unlikely to be concerned about a one off case of tachycardia, as it could be food or virus related, but as others have said, have a look at what you ate and drank that day (especially sugar and caffeine), keep a note of your heart rate and bp for the next few weeks, and consider a covid test. If it happens again, it needs further investigation - 24hr monitor and preferably a scan. Best wishes.
Edit: my 21 year old niece had covid a couple of weeks ago. Tested positive with no symptoms other than a bit tired with a slightly sore throat. Only had a test because she works in a shop and wanted to be extra careful.
Sorry, just realised you are awaiting a covid test result.