Hi, My daughter is turning 10 in July. She has started developing pain in the breast. I know this is a natural development process, however, the pain is only on the left side and also the pain lasted for more than three weeks. And, this was the second instance. She had slight pain a few months ago, but that lasted for may be a week or so. Also obviously the small bump is also only on the left side. Is this normal or something that needs to be checked with a doctor?