nipple discharge

a couple of days ago I squeezed my nipple and a dark green discharge came out. I went and saw my family care physician the next day. She said she had never seen this before. She gave me a breast exam and did not detect any lumps or abnormalities. She had the discharge examined by the laboratory and the result was 4+ bacteria, few wbc's. She then perscribed 500 mg of keflex (cephalexin)2 times a day  for 7 days.
(Other info: otherwise healty till now, no other symptoms other then breast tenderness, I am pre-menstal, youngest child is 4, I am in my early 30's)
She also did a culture but do not have the results back yet. Is she on the right track or shall I see a specialist? I am worried since she is only a family practice doctor and said she had no idea what this was but is treating me for an infection due to the lab results. I have been doing a lot of internet research on this and I can have anything from breast cancer to this being normal. I am at wits end here. Thanks

[annieappleseed]

Try checking out the National Cancer Institute site on breast cancer.  It is very comprehensive.

http://www.cancer.gov/cancertopics/types/breast

Good luck.