1 k != 135 ohms
Nevermind that 1 k is the wrong value. We can address that when he learns to wire his circuit correctly.
100 ohms. So 1k would "work" and use less current.
A LED can't burn your eyes or they wouldn't sell them.
They're bright enough to be painful and cause at least temporary blindness if you look directly into the LED.
Oh, I didn't know that. Maybe that's why I can't see out of my right eye...
Look at the value of LED current limiting resistors RN2A, RN2B and RN2C on the UNO. 1.0K.
LED has a minimum voltage to work..