if something hurts don’t do it find another way around it. For example if tbar rows hurt use a machine with a chest pad or use a bench to brace yourself for bent over rows. also work on your lower back extensions if your gym has the facilities and slowly build up those lower back muscles. As for pulldowns lighten the weight and think of your hands as just hooks on the bar and with a slow tempo pull with your elbows to lower the weight and slow on the way back up with no swinging, eliminating all swing to move the weight . As you get the feel for the exercise then increase the weight. Also look back through the pull videos so many tips and tricks to be learn from.