The big tipoff that you are tapering too fast is withdrawal symptoms. It is not uncommon while tapering off Effexor to drop too fast and have anxiety and rage–often flash rage—going from mildly annoyed to I-want-to-throttle-you in seconds. Rather than taking up smoking again (you've been off six months!), you can get relief from your withdrawal symptoms by reinstating your Effexor, going back to a dose where you didn't have any WD symptoms (you might even need to up your dose some). You stay there for some weeks to stabilize before attempting ANY more tapering. When you do begin tapering again, only reduce 5–10% (or even less) and wait weeks before reducing again. With all the stress we're under with COVID-19, maybe just forget about getting off Effexor for the time being.