My boyfriend has been having pains in his left side, under his ribs around the stomach area. It usually happens 2-3 times a day, for 5-10 minutes at a time. I don't know how long this has been happening, but it has been a while. He says applying pressure to it helps sometimes. And when the pains occurs he most of the time holds his breath and flexes his abdominal muscles. It seems like the pain is pretty bad because when it is occuring he sometimes groans. He is 14 years old, and I am worried about him. What could this possibly be? Is it something we should be worried about?