I have, to the best of my recollection, only ever used or heard:
He was bleeding from the arm.
... but my student informs me that she learnt it as:
He was bleeding at the arm.
The latter sounds a little off to me, but I couldn't tell you (or my student) why. I did a quick Google search, and found numerous instances of both. So my question: Are both usages interchangeable, or is there a subtle distinction I'm not aware of?
I'd especially like to know why the former sounds so much more "correct" to my ears, though I'm willing to accept that it is just me being weird.