frankly I don't see alarm bells. Nodes swell for all kinds of minor reasons: simple virus' that show no symptoms but get the immune symptom reacting, bug bites.... there is a thing called "shottty nodes" which means nodes that just stay enlarged for no reason. IF your nodes were a big deal, they would continue growing and you would be sick.
I get itchy under arm/s and itchy boobs. Underarms itch, often, due to an ingredient in anti-persperient. My nipple area will itch because I get hairs that grow on the edge of my aureolas. I will shave them off (carefully of course). when hairs grow, it can itch.
Finally itchiness, if paid attention to OR made into something sinister creates JUST enough reason for your anxious mind to keep the itching up. Swollen nodes often stay enlarged because the owner of those nodes won't leave them alone. It takes nodes a few weeks to go down on there own. . However if a person is fiddling around with them, it keeps them puffed up. It is sorta like a scab, if you pick at it, it takes longer to heal.
if you think your doctor is wrong, you can certainly get 2nd or 3rd opinions. I am sure you will be able to find a doctor who will just order additional testing. Lots of people here at AZ do just that. Now does that actually make things better? some people think it does... However what I see, more often than not, provided the person believes the new doc or medical testing, is they just end up cycling to a new illness. The time varies: could be a day, a week, a month, some make it a year