Floppybait, First you need to post about which angles you're working at. If you're working SD then you'll feel more at the base of the pubic bone, where shaft meets the pubic bone, because you're stretching the ligments that attach the penis to the pubic bone. This will lead to a lower exit point, which will then allow for the tunica to receive more stress. Then you would work at higher angles to target the tunica specifically, and even then it is hard to "feel" fatigue because this tissue doesn't have any great metabolic functions ie: lactic acid build up. What you will notice is a penis that feels more loose and almost sort of elastic to an extent. One of the biggest keys to Penis Enlargement is to learn how your penis feels from the inside out. Another important key is to understand the anatomy of the penis and where all of the important pieces are that you will be working to enlarge. Penis Enlargement is a journey and it takes some time to REALLY get acquainted with how things work and then even more so when it comes to what works best. Good luck and enjoy your journey.