Give Yourself some time my friend
There is no rush and it's not a competition
Try to watch Your own take or yourself in the mirror comparing to the instructor from original lesson. Aside from just focusing on bends give some extra focus on how the left hand works while bending. Your hand looks fine but I'm not sure if really the wrist is the main source of strenght in Your case. It's the vibrato You make which uncovered those little issues - trying to make it mostly using fingers. Sometimes when You rotate the wrist a bit more it helps