Yeah I definitely wasn't overheating, that's for sure.
Easy test Leesh - stick with the phenibut for a week or so and see if sweating persists. If so, stop taking it for a week and see if sweating goes away. If sweating goes away, start taking it again just to confirm it's the cause (as in theory, sweating should return).
If it appears to be the cause, speak to yer docta