I Have Had An Ultrasound Of Groin Area And Have

I have had an ultrasound of groin area and have been scheduled for CT. I also have large swollen mass in rt. arm pit. This too was ultrasounded. Would it be possible that these masses are swollen lymph nodes? I received a bad dog bite 10 weeks ago. Was wondering if perhaps my body has an infection going on from bite.
I will add that I had invasive breast cancer 15 yrs. ago. Also had thyroid cancer 7 yrs. ago. Not related. I am somewhat concerned. Should I be worried? I am hoping for swollen nodes due to infection.