What Causes Right Arm Pain After Injury?

I fel down stairs and hurt my upper right arm which was not X rayed at the time. I was told it was soft tissue damage. I paid for some unltrasound physio but it still hurts. My GP sent me to hospital for what I though was a cortisone injection. The Conultant sent me for an X ray and said there may have been a hairline fracture which has healed. he showed me an irregular thin raised area in the mid humerus area (as if someone had coated it with a thin layer of flour). he didn't say anything but is sending me for a bone scan and ultrasound. I am 50, just post menopause and I do weight bearing exercises regularly. i am slightly overweight but not obese