"Don't touch my nuts" is literally translated from Spanish as "No me toques los cojones".
You can use this sentence when someone is annoying you or when someone takes your piss off of you.
This is a little bit rude in Spain, so please use it only in a friendly environment.
Pau: "Hi Dave, the API is not working again!"
Dave: "Yes, it's working on my VM"
Pau: "DTMN, come over and take a look to it ..."
(1 min after)
Dave: "Ok, fixed, try again please"