Why am I feeling so scared all the time?? Is this normal?

A quick background. I'm a 42 yr old female, husband and 2 kids (17 & 11).
Have had bad health anxiety for about 10 years now. About a year ago I went back to work after many years being at home and it did wonders for my HA. It went away for a while and a few times when it came back I was able to control it. But the last few weeks I'm just sinking again.
I feel terrified all the time now. I'm going in to work later on and I'm dreading it. All I want to do is curl up in my bed.
My periods have been getting very heavy over the past year or two and I have a gyno appointment next week. As far as I know she will be putting a camera inside to have a look. I'm getting sick with worry over that now.
And I saw a bit of blood after a bowel movement over the weekend and that's still worrying me.
And to top it all off I'm due to check my breasts in the next day or two (usual monthly exam) and I'm dreading it. I've had a few bouts of bad breast HA over the past few years, last mammo was about 10 months ago.
I'm even worrying about my daughter who doesn't feel well the last few days.

I'm looking for some advice. I don't know what to do I feel so bad. I'm really scared all the time and these few HA issues are taking over.
It feels so disappointing to be back here again after having had a reasonably good year.

How can I rationalise my thoughts on all these things? I'm trying to convince myself it is HA and not a serious medical condition for any of the above issues.
Has anyone ever fallen like this with several HA issues at once, after having been doing so well?