Hi A-Z, I remember reading way back that benzo withdrawals can cause severe suicidal depression, not sure if the source was scientifically legit or what though. Plus it sounds like you're pretty much over the benzo withdrawal side effects by now.
Modern day cannabis, bred to be super strong, gives me anxiety and some paranoia, so I don't imbibe. Not sure if it's just a change in my biochemistry or what, but the old, much milder, 70's style cheap "commercial" weed in California never triggered any of that for me. Quite the opposite, in fact, it was relaxing and mellowing.
The following are not suggestions so much as stuff I find interesting on the subjects in this thread:
Depression: I was going through a questioning existence phase there for a bit. Mighta just been mid-life crisis that was about to end anyway, but around that time I started (successfully) busting with vitamin M for CH, and it not only removed my CH related PTSD-like symptoms, but I also found myself in a better, non existential crisis sort of head space. Of course it's all over the news as of late about psilocybin treatment for depression, and for someone in Oregon, or who could go there, I find the whole thing about Oregon will become the first state to formally legalize the medical use of psilocybin to treat mental health conditions in licensed facilities using registered therapists interesting and encouraging. I'm already thinking about trying to get a relative to head there for such treatment when available and possible. I would stop short of encouraging people to try to wing it with DIY psilocybin for depression therapy though.
Panic attacks: I have to wonder if the cannabis could really be a culprit 15 days after the fact? Meantime I found this bit about a new testosterone spray to kill panic attacks seriously intriguing. It sure sounds to me (someone who doesn't even resemble a doctor) like you've experienced some manner of lasting biochemical imbalance induced by a substance intended to be therapeutic for CH, that you can and will regain the balance you were enjoying previously, at which point you'll be so over these side effects, and will be golden.