Armpit Pain & Swelling: Causes, Symptoms & What to Expect

Question
Hello,
I went to the doctor today for a sinus infection. I then told him that I was having an annoying discomfort under my left armpit for quite some time.  I have a bump under the skin that hurts. It itches and burns and feels worse after I shave and put deorderant on.  It itches more when I sweat.  The Dr. looked at it today and said he did not see anything on the surface but felt a swollen lymphnode in that area.  I suffer from GAD and immediately jumped to conclusions and started thinking of cancer.  He said he felt it was a skin infection and put me on antibiotics.  He said he would see me back in 4 wks to see if I needed another round of antibiotics. I then called him when I got home because my anxiety was horrible.  He told me not to worry and he felt this kind of irritation was an infected lymphnode due to skin infection and irritation. He said the chance of it being cancer were so minute not even a chance on the richter scale(were his exact words!).  I have been looking up breast cancer and seeing all these things about lumps in armpits.  I am 30 years old and no family history of breast cancer. I just had a breast exam done Tuesday at my yearly check up. She said everything felt fine.  Does this sound like breast cancer or more of an infection?  My Dr does not seemed worried at all,should I be? I had this irritation for quite some time now.  It feels like razor burn but there are no bumps on the surface just kind of red.

Answer
If you are red there the skin IS irritated so there is probably an infection there. That the whole thing is painful also supports that it is caused by an infection. I agree with your dr.! If you continue to be worried a thin/fine needle aspiration biopsy of your node can show if it indeed is an infection/inflammation or a cancer!