We've done this type of ticket and connection in DOH frequently without issue but starting at ORD. We've even had good luck with the Qatar staff checking luggage through between the flights (though that is ORD Qatar staff).

I think it is a fairly common situation with award bookings.
I should add - the Qatar staff at your US airport start may be able to check you in and give you boarding passes for your onward flight. Let them know that you have a connecting flight