My first thought was "ouch." My second thought was, "What on earth is a thorn doing on my bedroom floor? Especially now?"
It's winter. The plants are all dead or dormant. I've had a few store-bought flowers in my house during the long cold months, but nothing with thorns like that. It looks a little like the thorns from my own rosebush, which I haven't even gone near since summer or maybe fall. I've vacuumed since then, and I've walked barefoot in my bedroom almost daily.
The only explanation I can think of is that it was hidden, wedged firmly in the carpet, pointy end down. When my foot slid, it managed to roll the thorn over and into my skin. Ouch!
Fortunately my heel has a lot of callous there. Even a long thorn mostly just hit dead skin. I squeezed it until a drop of blood came out, just to clean it out. Then I put a sock on and that was that.
But still - what a strange thing to find lodged in my foot! And how typical is it for me, that my first reminder of spring and growing things would be stepping on one and bleeding.... too funny!