Can swollen painful lymph nodes mean cancer?

Hi, I am new here. I recently noticed that my left axillary lymph node/nodes were swollen and very painfull and pain radiated throughout my left breast. I know that I have many fibroids already but I haven't felt anything out of the ordinary. After a few days the swelling and pain has gone down some. I did see my primary physician yesterday and she ordered an ultrasound for next week. I was just wondering if anyone has had this symptom related to breast cancer. I thought maybe it could be related to something else like Lupus which I have not been officially diagnosed with but have some of the symptoms. Thanks in advance for any thoughts on this.