Enlarged Lymph Node on Mammogram

I am 37 years old with 3 children and recently had my first mammogram. My radiologist and gynocologist told me I had an enlarged lymph node and that I am to return for a 2nd mammogram in 6 months.  I have been feeling a little more run down than usual and my menstrual periods have been irregular recently. I have also changed birth control pills about 3 months ago (lower dose).  I do not have any pain or tenderness in my breast, and I cannot feel a lump.  There is no history of breast cancer in my family.  I am concerned about waiting 6 months before taking any further action.  Should I do something sooner?  If the lymph node is still enlarged in 6 months should I have a different radiologist look at these films?
Thanks.

[Kevin Pho, MD]

Surgeon has kindly answered this question in the comments below and I concur with his response.  

Followup with your personal physician is essential.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Thanks,
Kevin, M.D.

[surgeon]

An isolated finding of an enlarged lymph node under the arm, with an otherwise ok mammogram, probably doesn't mean much. Lymph nodes enlarge in response to infection or inflammation; sometimes they never return to normal size. So this could have been that way for years, from some process that is long since resolved. It's a matter of caution to document lack of change, since the finding was on your first mammogram. Absent any symptoms at all, waiting 6 months is reasonable. If you are uncomfortable, one simple option is to have a physical recheck in 3 months. Also, there are findings in lymph nodes that tend to confirm benign status, such as a low-density (fatty) central area on xray. If that's the way it looked, it's even less of concern.