Arduino Nano stuck on uploading
So I plug the JST connector to the Vin and GND pin and the LED doesn't light up. I noticed that I had plugged it in the wrong way and I immediately unplugged it. Next I make another attempt and this time I plugged the pins entirely somewhere else, again I disconnect quickly. The third time I connect it properly and the power LED lights up (phew...)


Unfortunately Vin on an Arduino Nano does not have a reverse polarity protection diode such as the Arduino Uno PWRin


  Did I burn my board? 


Very probable. For more details please see "10 Ways to Destroy an Arduino". 

Cheers!