Hi, Am 21 And For The Last 7 Months I

Hi, am 21 and for the last 7 months i have been feeling some pain on my rib cage (lower) i went to doctor and at that same time i was feeling pain in the left best , did an ultra sound and my test came back normal. However that tenderness in the breast has stopped but the pain in the side which feels like a sore still remains. Please give me your best advice. I have been searching for answers. Thanks