Hi Peri,
Well anything connected to changes in heart rhythms does as you know only add to our already heightened anxiety. So of course it's natural to feel as you do.
I was diagnosed with a heart murmur many years ago, and has never needed any treatment. But because of this my heart often skips a beat, that makes me cough for some reason, and then the rhythm gets back on track. It's not a pleasant sensation at all, but I am very used to it.
It may sound odd, but I do get palpitations with strong non decaffeinated coffee, or indeed anything too caffeinated. Maybe worth avoiding these for a while in case this worsen the palpitations? I ask had them in the past if I got anaemia.
I can understand the worry of a brisk walk (always my preferred safety valve when anxiety hits) but maybe just a gentle walk would be good for you to get Outside and I always relax from this, calms me right down,somehow steadies me.
I am sure you have checked other threads and see most times these symptoms are caused by the joys of hormonal upheavals and nothing to worry about. Easier said then done.
You are right in checking this with a dr, I certainly would do so.
Wishing you well