Hi! Sometimes there's discomfort or even I don't know how to describe …

Hi! Sometimes there's discomfort or even I don't know how to describe it (it's not like pain). It's like a bubble inside with gas and pressing against me, and then it gives pressure in my lower back and makes me want to bend over and for something to pop and then it would feel better ? Sometimes when I press my legs towards my body, too, there's discomfort, like someone squeezed them and plus it presses on my penis and inside ? What could this be and from what? Please tell me. The doctor says everything is normal ?