Its pretty simple- moderate doses will induce focus and larger doses will make you cracked out dancing like a maniac (in your case). Have you ever seen a crystal meth addict focus? Me neither.
This is pretty basic so I'll toss it over to BDD. Also yes, the SNRI you're on probably did potentiate the stimulation to a degree.
okay, thanks. I just thought 90mg was a pretty standard dosage for like working purposes, so I was a little confused as to why it turned me into a dancing maniac, I guess I just found it weird my tolerance for it is so low...
i guess there's a first time for everything though
^context can play a huge role as well so if you took it at a party it'll have somewhat different effects than if you took it in a library with intent to study.
Also don't discount the synergy with the caffeine (red bull) and your SNRI that you take.