Dosage question

So I've started experimenting with phenibut because of my anxiety and depressed mood, which took hold of me a long time ago. First, I started with 0,5 g dose and felt no effect. Couple of days later I increased to 1 g - still no change. It might be due to my stature (about 6.4' and 210 lbs) so I increased the dose further to 2,5 g. My mood was slightly elevated, there was a little less negative thoughts, but still nothing spectacular. Today I took about 3 g, effect was similar to that after previous dose, maybe a little bit more noticeable but still it was just a slight "uplift". I took every dose at least 3 days apart, on an empty stomach with a cup of coffe. Should I increase to 4 g or stop at 3 and see if there is more noticeable improvement in mood after, say, 2 or 3 weeks?