Here's the deal. AVR pins are not meant to source more than 40mA TOPS, and you are sourcing nearly 14x that much. I'd be very surprised if it still works.
Odds are, because you're not measuring I and V at the same time, V dropped significantly to account for the excess current being drawn.
No, I'm not an expert, but I think that's what's going on.
In the future, ALWAYS use a current limiting resistor (preferably 300 Ohm+).