A very strong cramp-like reaction when I bend over. Could it be a hiatal hernia?

I have had the very strong cramp-like reaction when I bend over too far. Going on 5 years. And I also see and feel a hard lump. When I straighten my body back up, it gradually go ones away but takes a while. I was diagnosed with a hi as talk hernia. I haven't had surgery yet. But I researched hiatal hernias and found there to be different types. The one I think I have is the "Sliding Hiatal Hernia". This is where the top part of the stomach, which I've named the neck of the stomach, slides upward through a hole that was created in the diaphragm. It tends to slide upwards for a certain distance and then slides back down. When I bend over TOO FAR, and it only happens when I bend over far enough that my chest is almost touching my stomach, I believe that the neck of the  stomach is being pushed through the hole in the diaphragm. The diaphragm is a horizontal muscle dividing the chest from the lower part of your upper body. So, when your stomach is pushed upward through the hole (hernia), that part of the stomach is actually in the chest cavity. During my research, I learned that the entire stomach can possibly be pushed all the way through the hole! It said when that happens, the patient is often short of breath, because the stomach is often pushing against the upper lobe of the lung! 

I'm amazed that the answers we get when we ask why we have a cramp like feeling only when we bend over very far....have absolutely nothing to do with BENDING OVER!!! ........FRUSTRATING!!