Are Black Stools a Concern?

I have been sick since Sunday around 11 am, after a birthday party on Saturday. I ate cereal with milk Saturday morning and then ice cream [about 3 small scoops] and then about 3 more scoops later on that night.
Sunday morning, I had loose bowels movement. Then around 11 am, I had the worse stomach that I have had since I was a kid. I couldn't eat because my stomach hurt so bad. Then I had to go to the restroom so often [2 or 3 times an hour or more] and it was almost water. Monday morning at 1 am, I barely sat down on the toilet and had to get up and vomit. Monday all I had was tea and toast and that still hurt my stomach. Later on, I started drinking chamomile tea and it seems to cut the pain down.
Tuesday morning, I woke up with a headache but was unsure of my stomach. My bowels are still loose, but there is no stomach pain. I had chamomile tea and toast for breakfast and my pills for arthritis and Glucosamine 500 mg/Chondroitin 400 mg. At 9 am, I had 2 hot dogs. At 10 am, I had another bowel movement and it was dark, as close to black as ebony. Is there concern about this or this is the end result of what I'm going through?
I know no more milk products, at least not to the extent I took it.

You should definitely consult with a doctor. Causes of black stools include liver problems and blood in the intestinal tract. A doctor can quickly test for and eliminate any serious problems. "Change in bowel habit" is one of the indicators for seeing your doctor immediately.
As well as avoiding all dairy products, I suggest that you avoid all processed foods. Hot dogs are high in chemical additives. Stay with natural foods that are easy to digest: clear soup broth, preferably home made, by boiling fresh vegetables with a little chicken or fish; applesauce; well cooked vegetables. Fruit and vegetables are easier to digest when they are cooked. Rice is usually well tolerated in intestinal disorders. Brown rice is preferable for its nutritional value, but if it is hard for you to digest, switch to white rice. I recommend that you do not take glucosamine and chondroitin until after you have seen your doctor.