Let me outline what I've been through the past couple of months.
It might be a good way for me to get some perspective.
In October, I had abnormal bleeding. I went to the doctor. It was a uterine polyp. I've had them removed before. But this time I became completely convinced that it was actually malignant (they can be, but it's very rare). It wasn't, but during the two weeks leading up to my surgery, I certainly worked myself up into a state.
Then my two year old got a virus and ran a fever for a few days, and I became convinced it was Kawasaki disease, a rare syndrome I read about on the internet, which can result in permanent heart damage.
Then I noticed a spot on my tongue and became convinced I had oral cancer. I worried about it for weeks before finally going to an ENT specialist, who said it wasn't cancer.
Then the daycare teacher (also somewhat of an alarmist, I think) mentioned that my son's comp!exion looked a bit "yellow" and asked if I had ever had blood work done on him, as maybe he had a liver problem. Talk about a terrible thing to say to a health anxiety sufferer... but actually, I believe she has health anxiety also.
In fact, my son had recently had bloodwork done (when I thought he had Kawasaki disease), and it was normal. I took him back to the doctor anyway, who diagnosed him with carotenosis, a harmless condition in which children's skin takes on a yellowish tone when they eat too much beta carotene... so basically, we just needed to cut back on the sweet potatoes and carrots, and the yellowness went away.
Next, I thought I saw a lump in his groin area that might be a hernia, but the doctor could find no evidence of one. It was merely a lymph node.
Then I thought I felt a lump in my breast, but again, it was gone by the time I went to the doctor. The doctor said that sometimes cysts can come and go with your menstrual cycle.
Now my son is getting over another cold, and he seems extra clumsy and uncoordinated today. He actually walked right into a wall earlier while playing. I know it's because he isn't feeling well, he's tired and hasn't been sleeping well because of his cough... but my mind immediately latched onto the idea that he might have a brain tumor that is making him this way.
This is all in just the past few months! I am desperate for this to stop.
I don't want to believe my baby is sick. It hurts! It tears at my heart.
I'd much rather believe that I am sick myself, if I have to obsess about something... but unfortunately, I don't get a choice. I worry about myself, and I worry about him, and I have no choice in the matter.

I've always had anxiety disorder, and I've often believed I was dying of various types of cancer in the past... but the worries were sporadic, and I'd have calm spells in between.
But since October, I have had no respite from my anxiety. There has not been a single day that I have not worried that either my child or myself has a serious, life-threatening illness. I am having panic attacks and hyperventilating. I am useless at work. My whole family is sick of me. I cry constantly because I am so scared. I can't eat, and weigh less than 110 pounds. I am sleeping well, but it's only because sleep is my only respite from the anxiety, so I sleep at every opportunity. If I had the choice of never getting out of bed, I'd do that.

It seems something has caused my anxiety disorder to spiral out of control in a way it never has before, and it has entirely consumed me. It is riding me into the ground. I often do not want to live anymore, because I am so sad and scared.
I know I need help. I am truly desperate. I feel so alone, like there is a wall of glass separating me from the rest of the world, like I'm existing in some awful parallel universe, like I'm constantly walking through the valley of the shadow of death.
I hate the place I am, and I do not want my son to be here with me. Sometimes I think everyone would be better off if I was just gone.

Anyway, that's what is going on with me. That's why I joined this forum.