It's trying to tell you it's not happy and wants to go to the big bong in the sky ...........if all your other plants are doing fine with no issues at all I wouldn't worry to much about that one .......but there's numerous things that can cause that look IMO bugs included watering habits , soil/nutes ......but if I drop 20 seeds especially bag seed and one goes full retard and the rest are fine with no issues whatsoever in the same environment circumstances I name it after a few members here on Riu mostly flat earthers and a few flushers .....basically i don't worry about it .....GL