Plants arent tall in 5th week.? outdoor first time grow

hi im brandon this is my first grow. and my plant is grown out doors but i am a bit confused as i see other plants are much taller and longer in there 5th week were mine seems to stay to the growend, could this be because it is outdoor, over watering.? lack of sun.? please get back to me with information as soon as possible feel free to aim me : RawBerriezL
or call my cell phone ask for number. thank you