How was Rheese really feeling?

I am reading a book called, "Before My Heart Stops", by Paul Cardall. He was born with a congenital heart defect that was opposite of Rheese. Paul had double-inlet left ventricle and Rheese had double-outlet right ventricle along with other things, but they both had the same repair, a Fontan. The book is his story as an adult waiting for a heart transplant. A lot of it is from the blog he wrote while he was waiting but there are other parts that explain what happened to him as a child growing up with a CHD. As I read it I think back to moments with Rheese. One that I just read had me in tears. He said that before his Fontan he would get so exhausted just walking up the stairs and getting around school that it made him nauseous. For the last few months of Rheese's life he threw up quite a bit and we couldn't find a reason why. Many times it happened at school and he'd have to come home. It just makes me wonder how bad he really felt but didn't tell us. I knew he wasn't feeling good and was trying to find out why but I know I didn't get how bad it really was. A little boy in his class told his dad who then told us that a couple days before he died he told him that his chest felt funny. The boy told him to tell the teacher but he said something to the affect that it does it all the time and will go away. I had NO idea this ever happened because he never told me. I wish I could ask him how long it had been going on. Maybe he had lived with it his whole life, I don't know. He also used to get really grumpy, I mean REALLY grumpy. I now think it was because he didn't feel good and that's how he reacted to it. I used to just think he was being a stinker. Oh, there are so many questions I wish I could ask him. I'll just have to wait. One day I'll have the answers.July 2008 after getting his pacemaker.