What Is Causing Pain In Rib Cage Near Sternum? Area Swollen. No Injury. All Reports Normal

I am a 29 year old female, 5 8 , 160 lbs. I have pain in my right ribcage. The pain seems to be worse near my sternum, then radiates out, underneath my breast . I also get some pain in my sternum (though it doesn t hurt when I press on my sternum). The pain has been constant for 17+ months. I have been to my doctor and had x-rays, blood tests, an abdominal ultrasound, a barium swallow , an ekg and a HIDA scan, all normal. The pain does not get worse when I breathe , which makes me think costochondritis is not the case. The rib that hurts is also swollen-I can feel it w/my hand as well as when I lie on my stomach. I ve had no injury to the area. I ve been to several chiropractors (one tried to tell me whiplash was causing my pain), but my pain is usually worse after getting adjustments. Please help!