I agree with what @jiujitsu and @ggrouse have said. The reason you get promoted is because you have already earned it and your professor knows best.
That being said, every promotion I have ever had (I never considered stripes as promotions but they definitely are when you give it some thought) I have felt a little undeserving. I am pretty sure that feeling never goes away and is part of the staying humble, keeping your ego in check, and constantly pushing yourself to learn more.
Your next belt will come when you have earned it and my advice would be to set goals around competitions, positive patterns, and applying what you have learned on the mats to help achieve success off the mats.
Belt is for keeping your pants up and your gi closed!
Congrats on the stripe!
I agree with what they say as well. I'm just a bit hard on myself but in a good way as I can use it to my advantage to continue to improve. I've never been concerned about the belts nor being promoted but just enjoy the process of learning such an incredible skill. "Belt is for keeping your pants up and your gi closed!" Love that!! Thanks mate.