Below, you'll see any text that was highlighted with comments from the reviewer.
It is a bit disjointed, but that's to be expected with this sort of prompt. I'm not quite sure how to describe the tone/ mood. Surprised maybe?
The line "that hurt." It felt 100% natural with the flow of the writing and didn't seem awkward at all.
I like "I was in pain though" on. The flow of the narrative is very natural.
I really think you nailed the ending. The highlighted parts are a little shaky, but overall, it's a very good piece and a great response to the countdown prompt.