Electrical issue - 2008 Tundra

While driving earlier tonight I dimmed my lights. A couple dash lights came on and the speedometer bottomed out then went right back to my speed.
After coming out of the restaurant, truck was DEAD! Tried jumping it off. Now, it wants to turn over but won’t crank. I had to manually lock the doors when I left it, because the doors wouldn’t even lock with the key. I just replaced the alternator in Sept. 2020.

Battery? Electrical system?

 

I would side with battery... check your grounds first, as it may seem adding additional load drained the battery... I'm no electrician but adding load may indicate issues with the electrical... cheapest is to check your terminals, battery and then revisit your alternator, by getting it load tested.. you may be able to do bothe battery and alternator at the same time in some places..