I have health anxiety too.
You might be surprised, Magpie, mine dissapeared when I was pregnant as I was just so focused on the pregnancy itself.
I often find mine flares when I'm not happy about something else in my life, tuscanrose. Perhaps have a think about that? CBT didn't work for me except for this one little 'activity.' When you wake up and start worrying, think to yourself, ' I'm not going to worry about it now, I'm going to worry about it at 7pm. I will not touch my glands until 7pm and then I will give myself 15 mins to worry.' It's hard, but it can help.
I also went through the whole lymph node worry. One doctor said to me, 'if it was something bad, you WOULDNT have to go looking for it. It will grow and grow until it's the size of an orange and you wouldn't be able to miss it.' I have 2 in my neck that I can always feel that are about the size of kidney beans. I can feel them deep in my armpit and one is the size of a pound coin!
I can feel them in my kids neck (I don't touch them, have noticed in passing).
There is a web forum for health anxiety called no more panic but in all honesty, it makes my health anxiety so much worse reading it.
As someone who goes in and out of episodes of health anxiety (in a bad episode at the moment), my advice would be to stay off anything online and find ways to make yourself as happy as possible.