millipede flailing around

i couldn't really get a video without turning my phones flash on, but today i went to check up on my millipede (juvenile narceus americanus) at night and i noticed she was violently flailing around in the corner and it really freaked me out. usually when i see her she's just crawling around like normal so im confused why she'd be doing this. the thrashing seemed to have lasted <1-2 minutes but i just left so i have no idea what shes doing now. is there anything i should be checking for? parasites, humidity/moisture, etc? could it be stress from something i'm doing wrong?? i'm just really worried tbh