Yea that's awesome to put 12 pounds on in 7 weeks but the weight shouldn't stop now. Your test is just starting to get its peak so strength should start goin up even more. I know from my own experience that more gear does not make a big difference, my first cycle I had so much test I went up to just about 1000 mgs a week at the end cus I thought it would make me put more weight on but it didn't. Being your first cycle 500 mgs a week should be awesome for 15 weeks. Throw in about 1000 more caloriesd a day right now and watch how fast you grow. U already put 12 pounds on which means u need more carolies just to keep that weight on let alone add some more...try it out man, I'm just trying to explain what hapened to me so your next cycle u don't need a shit load of test to see gains. Take it slow, I hate saying less is more, but its true.