Brief Answer:
I would recommend as follows

Detailed Answer:

Hello,

Your high heart rate could be related to anxiety. I don't think that this high heart rate is related to the propranolol that you took two days ago. I would just recommend you to try to take some deep breaths and close your eyes, until you will calm down.

Anxiety is playing an important role in all this clinical scenario. Is the heart rhythm regular? I would like to know your age and past medical history. If the palpitations or shortness of breath persists, I recommend going to the ER for a physical exam and some tests:

- A resting ECG
- Complete blood count for anemia
- Blood electrolytes for possible imbalances

Considering these episodes, I would also recommend discussing with your attending physician on performing some further tests:

- A cardiac ultrasound
- Thyroid hormone levels to investigate for thyroid gland dysfunction
- An ambulatory 24-48 hours ECG monitoring to examine your heart rhythm trends for a prolonged time and exclude possible arrhythmia.

In the meantime, I would recommend you to avoid caffeine intake and focus on your anxiety. Meditation and Yoga can help improve your situation.

If you have any other questions, please don't hesitate to ask me again!

Hope you will find this answer helpful!
Kind regards

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