no man wait! You have to let your body come back to its regular self. You've been supplementing the natural test your body makes with the sust. Pct helps your body get back to normal so to speak faster than if no post cycle therapy (pct) at all. Once thats done you can then do another cycle. People always say x weeks on x weeks off but that really depends on the cycle you did. Test (in most cases) takes a few weeks to fully get outa ur system. Then when post cycle therapy (pct) starts you should always wait until your system is back to normal and that depends on your body. So i.e. In you case with Sustanon (sust) 13 weeks on is easily 15-16 weeks off. Shorter esters like tren more fit the bill of x weeks on x weeks off, but i still would wait a little longer to make sure. I'm starting a tren cycle myself. A six week shortie but i'll tell you i'll wait at least another 2 months after my last shot to consider another cycle. This is the thinking you should have; but, its ur body and you can do whatever u want.