So I went and got my air filter housing changed today

You sure the bulb didnt burn out when you turned the lights on? What kind of truck ?

 

Check your rear differential

 

What kind of truck?
Really?

 

This just gets better and better. I think it's a trailer issue

 

This was my favorite part about being a wrench. Put brake chambers on a trailer and when the windshield wipers stop working it was somehow something I did because I touched the trailer lol.

 

Mechanic could have leaned on, or somehow accidentally
disconnected the wire to the bulb.
You can troubleshoot this yourself.
Put the hood up.
Find which bulb it is.
Pull it out and look at the filament in it against a white background.
Confirm it is complete, and connected on both ends.
Take to the other side and swap bulbs, and turn on.
If bulb lights on other side of truck, its the wiring.
You may discover a loose connection when you are doing this.
Good luck, and get back to us with what it was.

Then check your blinker fluid reservoir level sensor.
(Couldn't help it; had to.)

 

Willing to bet the bulb just burned out and OP just wants a free bulb by blaming the mechanic lol.

 

Doubt it.