Let me at the outset tell you that most common cause of palpitation is anxiety. With your heart related investigation showing nothing abnormal, this is further substantiated. Having said that; your hormonal imbalance may be the culprit too here. You had a really big year, so obviously they too kept the hormones working overtime.
I would suggest you following;
1) Cognitive-behavioral therapy (CBT) and operant-behavioral therapy (OBT); done by a psychologist.
2) Relaxation training and biofeedback.
4) Acupuncture and acupressure
7) Group sporting activities
8) St. John's wort
10) Valerian root.
You may get an Holter 24 hours monitoring. This takes heart tracing round the clock by a small device taped to your chest. This may rule out any arrhythmia, which may occasionally be responsible for the palpitations.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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