Bending lower stems 8 weeks flower

hey everyone just wanted to post some pictures here of some lower stems on my plant that are bending down. anyone know why their doing this? Im almost 8 weeks flower and planning on going to 10 or 11...
my grow is 1 400w metal halide...3 plants...soil...20-20-20 for veg...15-30-15 for flower...closet grow...
thanks for the replies and please let me know why you think there doing this and some solutions///

tall skinny and top heavy im thinking try to tie a string around all the stems the strong ones will hold it up

Buds gettin to heavy. Tie the branches up so they get mo light and dont break.

Sir KK

That's 8 weeks into flower? Your doing something wrong buddy. Wrong lights, small pot, high temps. What are your conditions?

65-70 at night...80-87 in day...soil...15-30-15 nutes(dont put tht much in)...1 400w metal halide, 2 40w fluro tubes, 2 15w cfls...small white painted closet...buds are pretty small at bottom but there 5 1/2 foot plants so theres way more at top... lol i aint doin tht much wrong! good enough lights, ~2 gallon pots, pretty good tempss

keep in mind these are stems coming off the main stem not the full plants lol

400w MH, we have a Bingo....

what did u veg with? looks like your nodes are super streched out

yeah they are just on that plant unfortunately...vegged with 2 40w fluro tubes full spectrum and 2 cfls 15w for 10 wks