Welcome! Likely just a bad Nox sensor. Should be fine to drive until you get it back to the dealer. Emissions is something that can give problems early and quick.. just part of modern diesels.
Good info here.. and yep it's easy to change the oil. At least you know it's done right, and it saves you some money! The dealer (and even quick lubes) love to take advantage of customers because it's a "diesel".
Welcome. Glad you're under warranty, and even better since the dealer maintained the truck. They really can't point any fingers now..
Keep us updated on the engine progress.
FCA recommends it to be used under 30, as noted here:
https://www.ecodieselram.com/forum/threads/r51-fca-recommends-a-winter-front-cover-for-colder-climates-with-ecodiesels.521/
Here's a great thread for you! Welcome to the forum (y)
https://www.ecodieselram.com/forum/threads/ram-ecodiesel-oil-change-information.318/
also this: http://www.ecodieselram.com/forum/threads/psa-fca-changes-oil-specification-requirement-for-ram-1500-ecodiesels.820/
Good info.. looks like it's for Windows and/or Android software. Looks like $49 for the cost, and the adapter is here: http://www.alfaobd.com/index.html