Brief answer....seems to be benign muscle twitchings
Detailed answer....
Hello,
Thanks for the query.
I have rad your query and understand your concern.
This type of fluttering sensations are encountered very commonly by people from all age groups. Although mostly caused by muscle twitching but sometimes gets confused with palpitations and arrhythmias.
If your blood pressure is fine and there is no discomfort like sweating or rapid pulse,then it appears to be muscle twitching only.
Such twitchings could be without any reason or due to anxiety or stress  and may stop in next few days of their own OR they could be due to hypothyroidism or deficiencies of calcium,VIT D VIT B 12 etc.
Just relax and wait for couple of days more.
In case they persist,then consult your doctor and get investigated for above mentioned causes and also get the ECG done to rule out any heart involvement.
I hope it helps however you are most welcome to revert to me for any further query,
Best of luck
Thanks

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