What is an energy drink? Just out of curiosity.
It's not like it's a high risk venture, really, if you start in your apartment, is it? I mean you can start very very part time while you still have a "regular" job. You will not need to produce more until you have sold your stock, so you'll spend more time & money only when the previous production has already been paid for, more or less. Depending on how quickly the next lot goes you will know if there is a real interest in your product, if demand is constant or increasing or decreasing, etc.
I see this as a pretty low risk venture, so bottom line is "why not?" or "what have you got to lose?".