Brief Answer:
It can be heart related issue or panic attack.

Detailed Answer:
Hi dear

Rapid heart beat is called tachycardia.

It can be feature of heart related pathology or psychological anxiety.

I want to know certain information.
like

Time of it?
Duration of it?
Continuations or episodic?
Whether it occurs in sleep?
Any associated features like sweating, heaviness in arm etc?
How it is resolve?
Any past history?

As my opinion you have to go for tests.

Tests include heart profile like ECG, ECHO etc.

Have you done ever??
It is routine screening which we have to get it done every yearly as prophylaxis.

1st thing would be to rule out heart related pathology.

If all reports come normal then we have to think about psychological evaluation.

In psychological assessment primary area of investigation is panic attack.

Panic attack has similar features as heart attack. But only difference is in panic attack there is no pathology in heart. Heart is working normal. All arise from mind due to anxiety.

But be on safer side heart related evaluation is must before we can think about panic attack.

Treatment of both are different.

For sleep disturbance, it suggests anxiety and due to this you are not able to sleep.

But consult physician first and will go for reports, he will guide you further.

If you have done all reports then revert back to me along with above asked details.

Happy to help you.

Thank you.

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