It should be. Although it certainly bears mentioning that 10 grams is an absolutely ridiculous dose; that's the equivalent of 40 capsules, which is something you don't realise when you're using it in powder form. Even 5-7 grams is excessive; the time you waited between doses and the fact that you were never using for too many days successively are probably the only things that spared you from withdrawal symptoms (which can get quite nasty, even if not as fiendish as benzos).
Your idea of switching down to a dose of 2-4g is definitely a good choice. If you're only going to be using phenibut occasionally, 4g should be fine; if you're looking to use it daily in a sustainable manner, you should generally be considering doses around 1.5-2g, and never higher than 3. Contrary to what a lot of people claim, phenibut can, at least in my experience, be used regularly and sustainably without problems, as long as you keep to reasonable doses.