Can you get Organ damage from light Running, especially if you have a weak body?

Hi all. I’m male age 30. i have skinny limbs and a weak body . i kinda look like people with marfan’s syndrome. I’ve done exercise all mylife, and now with knee injuries etc, although not much, i still do enough exercise to keep in shape.

But, I’ve noticed since some years ago, when i run( even though it’s light) or even walk..my chest starts hurting. it feels like bruised.

Well yesterday i did light running for a long distance. Nothing you would think would kill a person. Except it did something to me. Cause i was having chest pain. it felt bruised and then i had to keep stopping. but i rested and then kept going.

Well, today(the next day) after the run, i feel like farting feeling and movement inside my chest. sometimes i even heart sounds.

I wonder if i overdid it yesterday?
It’s hurting alittle bit but not that much though.

Can this be that i had some organ damage? or what can it be and can it heal.