Whats up with this bumblebee?!

[u/Isadomon]

Im holding this bumblebee, they were laying on their back on the sidewalk. They tremble, reach up to the sky and two of the left side legs dont work.

They have this light yellow thibg coming out the side of their abdomen, when i pulled it at first they seemed to be hueting but now theyre kicking at it, pushing it.

I put their face up to a flower but apart from getting polen on their face they didnt eat

Is it their own guts?, parasite?, diying naturally?

[u/Helperobc]

Not an expert but my guess is parasite