This weight is very light for you. Your set up is decent. Areas for improvement: 1) Squeeze your chest up tighter to get your back tighter. 2) As you initiate the lift, push the floor away from you with your feet. You, currently, are trying to stand up by lifting your back/chest. Which is leading you to not fully extend your knees soon enough: watch the bar path, and note how you have to move the bar around your knees, instead of pulling the bar up in a straight line; you want a straight line. As the weight gets heavier it will be harder to move the bar around your knees, so you want to fix this issue now before the weights get that heavy. Also, for your low-back safety, you don't want the weight/bar drifting forward of mid-foot with heavy weight; the farther forward the weight gets the more stress it puts on your low back.