Your testes naturally rise up or fall down low depending on temperature, trauma and ejaculation. When your testes shrink due to steroid use, they can rise up a bit farther than normal and can tuck themselves next to the base of your penis, where it attaches to your body. They are able to rise quite far up, especially during/after ejaculation. However, your testes will not rise up into the area of your stomach unless you have a hernia.