Am I about to give my plant a nitrogen overdose?

Hello my friend, you do not need to do anything. You are not overfeeding, you give the right nutrients and the small Nitrogen toxidity is not worth flushing the soil and risk bigger problems. The plant is still streching so she will use her Nitrogen and the Nitrogen inside the soil. Just keep doing what you are doing already! 💚

Give her a good flush, here is pretty good video about nitrogen issues https://www.weedinapot.com/post/nitrogen-issues-in-cannabis

Close , but still on last verge of healthy. That wrinkle and later maybe rusty spots aka calcium more from mechanical ( best case ) damage or watering regime aka overwatering slightly. Nice girl ! Dont overdo !