Depends on what kind of pain it is. If it's a sharp pain then no. If it's more of a burn then yes, that's just your ligaments being stretched. Lig gains usually come first, and according to some they continue coming (see DLD's routines), but there's also some gains (in length ) from stretching the tunica.
Not if it's a sharp pain that does not go away. Mild pain is ok. I have mild pain/soreness in the base area and/or the shaft after intense hanging the next day. That to me, is a sign that I am doing something right, and stressing the tissues the way they need to be stressed.
I am doubtfull that many guys ever really "max out" any certain area. In other words, potential ligament, or tunica gains. Especially when you consider than few guys ever want more than an inch or two in length gains. Now, maybe if a guy had gained several inches in length , he may be on the way to 'maxing out' on lig gains, but the tissues of the penis are like tissues in other parts of the body. Skin, and tissue will stretch farther than most people realize. Try going to Uganda or Ethiopia and telling one of those tribesmen that they cannot possibly stretch their lips any farther than a couple inches before they "max out". .