It's only 7 weeks into your first cycle - for me - that's right when things started to happen...
For my first cycle I seen gradual gains up through week 6 and week 7 was the "ah ha" moment.
If the diet isnt right and workouts aren't intense enough - you can pipe in 750mg if test a week and you won't see anything except the sides - this would be my guess.
You could contact Z and if there was an issue he'll take care of you...
But just like DPR says - I doubt it's under dosed - I've ran many if Z's products and never felt anything was under dosed - but that's not to say it coulnt be.
I would guess the diet and the intensity of the workouts - plus proper rest.
I also wouldnt use the sides as a way to judge the results as I don't really get oily skin and stuff like that - everyone reacts or responds differently.