Pulsating pain in butt-hole while going bathroom?

I needed to go poop, so I go to the bathroom and sit there for a moment and suddenly there's this kind of pulsating pain pushing against my butt hole from the inside.

or maybe it was not pulsating, not sure how to describe the pain but it felt like pressure, not burning, just pain pushing on my anus from the inside. It hurts!

i started breathing out rapidly through my mouth, it sounded like when a girl is about to give birth.
What the Fluke is that pain? And why?

Has as this happened to you? Anybody know why this happened?
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+1 y
I pooped fine. It was right after I pooped that this pain came.
I've never had problems going to the bathroom, and it was not hard to poop and there was no pain to poop.

I eat healthy I do eat a lot of fiber and I do excercise.
This is not constipation. It doesn't hurt to poop and I don't take long to poop. It was just a pushing pain from the inside pushing out. I want to know what that was and why it's happening.
Pulsating pain in butt-hole while going bathroom?
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