One year old only weighs 17 pounds. She's active and loves nursing. She's sometimes interested in solid food, sometimes not. Should I be worried?

It depends. Your daughter's doctor is the best one to know if this growth rate is right for her. It depends on how she has been growing, how her height and weight correlate, and how healthy she is. If she is doing well, just keep offering foods (try giving breast milk only after she eats solids)- the amount she takes will change from day to day. Offer more finger foods- she may want to feed herself more now.