First time flying Qatar airlines. (I have no status on any airline)
Going from US to Qatar.
I booked via AA because they were $80 cheaper for the same non-stop flight.

Got AA booking code. AA also gave me Qatar's confirmation code.
I checked in at Qatar's site. They won't give me a boarding pass. I need to visit a counter to get that.
I'm assuming to verify passport?

Anyway, do i goto AA's counter since i bought the ticket from AA or goto Qatar's counter since it's their flight to get a boarding pass?
And do i need to talk to someone or can i use a kiosk?
(I don't want to wait on line at check in because i'm not checking in anything. I'm just bringing a 22" carry-on and a laptop bag)

Edit:
Answers- Qatar counter, have to give passport to agent, no kiosk to scan passport like some other airlines, and they weighed carry-on but not laptop backpack.
Also did not measure dimensions of carry-on