Help Understanding

I found what I felt to be a lump in the right breast axilla area only when I extend my arm over my head can I feel it. I also had breast pain which is how I found the lump. Went for a breast exam at the MD office. Sure enough she said she felt the lump in the axilla however she did the exam with me sitting up(strange). She sent me for a ultrasound. Nothing was seen because the radiologist said it was so far back and probably deep in the chest wall(the pain and lump). So MD sent me for a mammogram. It showed mild Parenchymal Asymmetry with Biards catogory 3. I have to have another mammo in six months. Is this anything to be concerned about what does all this mean? Can't get into see MD for 3 weeks as she is on vacation. Please help. Still having pain in that area but anxiety is worst.

[Cleveland Clinic]

Dear Jkimmie,  A BIRAD 3 means that the abnormality is likely benign and that follow up would be recommended in 6 months.  Over the internet without being able to evaluate including physical examination, questioning and review of films it is difficult to advise any further.