Love the daffodils in your avi!
Regarding the weights you are starting with ... you have to do what you are comfortable with, but give yourself some credit!! The upper back muscles are large, and a gallon of milk weighs just over 8 lbs. So doing rows with 3 lbs or 5 lbs is in all liklihood too light. Pick something a little heavier than you think you are comfortable with. When you bang out your reps with it, you'll feel soooooo good! If you feel better (ie more safe) starting at lower weights, keep in mind that you want to increase them every workout ... especially as the reps drop (fewer reps means technically you should be able to do more weight).
Keep it up!!
