I'm referring to PB0 and I verified that I was controlling it because I removed the digitalWrite(0, HIGH) command, and it measured 0 V. Why does it matter that PB0 can also serve as AREF if I'm not using an external ADC reference? I added "analogReference(INTERNAL)" to see if it would make a difference, and it didn't.
Pin PB0 is not connected to anything and my meter measures other voltages correctly. I tried a different Attiny85 chip and I get the same result.
Not sure if it's also worth mentioning that I'm using this Tiny AVR Programmer: https://www.sparkfun.com/products/11801