When is too much?

Ok guys, been going 500mg test e 8 weeks, thinking of going 750 for 4 more for a total of 12 weeks. Is this too much? I almost feel addicted, I was supposed to stop at week 9 but the gains were still coming(slowly, but still coming), and I know 12 active weeks is really 14 weeks(since test is active up to 2 weeks after last shot). Is this too much? I know standard is 10 weeks for test. Whats the longest test cycles most people are running safely?

Is this your first cycle? If so just run it @ 500mg for 12.. there's no need to increase the dosage...

I planned a 20 weeker and am going on week 26 now,,, I will stop around week 30...