Hi, I recently purchased an Arduino Uno R3 and have had it for a few days.
When I first got the microcontroller, it was working fine and the pin 13 LED was blinking when the blink file was uploaded. However, I was in a school lab today and when I attached a breadboard circuit to the Arduino's PIN 13 and GND, the circuit would not function (was a simple resistor and LED circuit). After this happened, I tried to reupload the blink file, but the LED would not light up again! The two lights below marked TX and RX blinked as if something was being uploaded, but the pin 13 LED does not light up at all. Also, when I attach a shield (that doesn't use pin 13), programs works fine with that specific shield.
I'm pretty sure I fried pin 13. What should I do now?? Is it possible to replace the LED or can I just live without it?
p.s. I was running windows
p.p.s. I was also using a different voltage source when attaching the circuit. It was at 12V so I'm 75% sure I fried it