Heart attack usually gives dull or squeezing pain which radiates to the left arm or jaw. Fear of death, sweating, dizziness can appear.

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Brief Answer:
Rib nerve pain gets worse when moving.

Detailed Answer:
If the pain is well localized (you are able to point the spot where it appears), sharp, more intense when moving or breathing, less intense when you hold your breath its not a hear attack.
Such pain is caused by rib nerve irritation. It is sometimes called costochondirtis. Due to rib nerve irritation the pain appears. Such irritation can be caused by local inflammation, spine problem, however in most cases there is no particular reason for this issue. Even long staying in one position (like sleeping or driving a car), lifting something can trigger such pain.

Heart pain does not get worse when moving or breathing. It very often radiates to left arm or jaw. It is also dull and not localized. When you hold your breath, the pain is still the same.

For rib nerve pain, hot bath, painkillers (like Diclophenac) or even a massage can help.

Hope this will help. Feel free to ask further questions.
Regards

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