What is wrong should I call a doctor?

random shaking and i can feel my heartbeat for no reason i was a little stressed earlier but am fine now and it came on randomly should i be worried i am in no pain i popped my neck earlier but it was normal and i kept moving it around to try to pop it could it be a heart issue or brain or a panic attack i googled it it said could be heart or brain or just a panic attack but i don’t understand why it would happen randomly could a panic attack happen randomly i do have ocd and adhd

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+1 y
also this has happened before and happens every so often and i get very worried since i was 13 it has happened and it usually goes away after a hour or two or i sleep what u think it is
What is wrong should I call a doctor?
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