You are saying all the classic things an anxiety person says.
Reading your posts I see me of 5 years ago in you like a reflection.
For example "I did this, but the symptom is still there .... therefore I frett more!"
Anxiety symptoms are very unpredictable, you can have suffered something that's at the root of it, get symptoms, get calm, symptoms still exist for a long time, even stay calm, symptoms carry on, then over time gets better, there is not a simple switch.
I know it's easy to assume "well anxiety - pfft! that would just be too good to be true!" or 'well those other people on this board, those hypocondriacs, yeah they may not have it - those poor people aren't like me though, cuz Im different I actually have some fill-in-the-disease"
The fact you are jumping between diseases is also a classic anxiety tell tale to me.