I have been suffering with crippling health anxiety about my DD10, who has a swollen gland in her neck (thread here).
In the end, I made an appointment for myself to see the GP to confess my fears and see what help can be give. I explained my anxiety about DD, and the effect it has had - checking her all the time, fear she has leukaemia or cancer and is going to die, not sleeping or eating etc etc.
I suppose I just wanted the GP to tell me she will be fine. But of course she didn't. She said the chances are a bit like winning the lottery - it happens to someone every day, but not me. She suggested I increase my dose of anti-d's while DD still has the swollen gland, and while they 'do what they have to do' to investigate it.
Meanwhile, she got me to fill in a depression questionnaire and is referring me to the mental health team for an assessment. The waiting list for CBT is huge, apparently.
So, I am not any further forward and all my fears about DD have re-sufaced, just when I was beginning to calm down.