Eric is absolutely right. The reason you want to add reps with each workout (getting at least one more than the previous workout) is that it slowly forces your weak arm to get stronger. Taking a weight you can do with proper form for 5-6 reps and adding one rep each week will get you to the point where you slowly add weight to the bar (once you can do 8-10 reps with good form). Good luck and keep your chin up as it will all work itself out.
