Meds
Adam, you might also have what is known as a "milk allergy" which is an immune system problem where your body will attack the milk proteins, present in cheeses and ice cream as well, and cause pain. There isn't really any treatment for this, although some allergy medicines might help a bit. If it is indeed lactose intolerance there are some over-the-counter meds (Lactaid) that you can take to reduce the sickness after consuming lactose-rich products. Since you seem to have such overwhelming pain, it is probably lactose intolerance.