Can the lymph nodes in your armpits hurt a few days before your period? i can't feel them but under my arms are a little sore. no visible difference

More likely breast: Rather than lymph nodes, I suspect that you have a bit of "ectopic" breast tissue in your armpits. This is not terribly rare. Some women have breast tissue in the armpits. Just as the rest of your breast can get swollen and hurt before your period, so can this tissue. Best to see a doctor at this point in your cycle to be sure.