I thought I’d posted this earlier, but I guess I never hit submit!
I’ve heard the Volcano can be a bit harsh...it probably depends on how high you set the temp and how long it sits in the bag though, among other things.
Since you like wide-open airflow, the FlowerPot is very open and I think it’s another great option in that respect, so if you’re looking for the best desktop I’d take another look at it.
I’ve got that from micro-dosing...I actually seem to have less of it with moderately sized hits off of a larger load, but I think what helps the most is CBD. I’d continue to use what you have now along with the Indica and that should go a long way toward dealing with those issues.
Other than that slow, deep breaths may help, and if you don’t have a real reason to worry about heart problems, just telling yourself it’s not real and you’ll be fine as soon as you stop freaking yourself out may help too.
I wish I had better advice, but I haven’t quite beat this yet myself so I clearly don’t have all the answers.