I believe there are basically two types of anxiety, having two different causes, but they can sometimes be quite similar. One is more psychotic, the other neurotic, one based on knowing/conviction, the other on not knowing, doubt (trauma and phobias might be of the latter type, but maybe not).

The former can cause the latter, but not—directly—the other way round. The latter form of anxiety can cause psychotic perception/problems, psychoticism or psychosis, and thereby causing the former which can cause the latter and so on.

The latter type alone can directly cause more of it: it can be self-supporting.

All (can) create positive feedback loops, though I believe the perceptual-appraisal and mood or emotional changes, psychotic issues/disturbances, psychoticism, also lessen anxiety.

It's rather important to see whether there is any (maybe somewhat residual) anxiety of the former type, because doubt can be dealt with more easily than convictions and because the former can easily "reinvigorate" the latter.

The former type of anxiety is best treated with antipsychotics, pharmacotherapy, the latter type with psychotherapy (which you might do on your own).

As treating the latter type probably involves more exposure, meaning you should not try to lessen the doubt, by thinking/rationalising or asking for confirmation/affirmation, basically, you can't really overcome the latter type of anxiety without treating the former type—if you deal with both types.

I think panic attacks are suggestive of a stronger self-sustaining anxiety of the latter type than a feedback loop involving anything psychotic. It doesn't mean the former type doesn't exist or might not be what starts a panic attack.

Dread can be doubt or conviction, something that might go wrong or will go wrong. I do think if it's very really abstract and intangible I'd say it might be more of a psychotic nature, but I don't know.

To determine whether it is maintained by anxiety of a psychotic nature, I'd suggest trying an antipsychotic for at least six months. And learn to love uncertainty, if that is a problem.

Another approach is desentisation. The most difficult part is fear for anxiety/fear. If you distract yourself enough, you remove some of that fear.

You might also want more challenges: results matter more, leaving less room for doubt.

I (especially) wouldn't use meds for anxiety of a more neurotic or non-psychotic nature. But maybe it's best for you. Then I'd only use it for a few months.

Hope some of this might help.