I am 14 year old male. I weight 110 pounds and have been trying to gain weight recently. I have noticed these problems from like 2 years ago! I think I have many health issues but the one that really bother me the most is my pain in the middle of body. It is between chest and stomach:

http://i1021.photobucket.com/albums/af338/rcclassiks08/715px-Human_body_features-1.jpg?t=1269833179

http://i1021.photobucket.com/albums/af338/rcclassiks08/anatomy_of_human_body-1.gif?t=1269833562

If I tap that part slightly hard it hurts. Same thing with the my right ribs. Anyway, I was playing basketball and someone passed me the ball and I caught it against my right rib and it took my breath out for like 1 second. It WAS NOT hard at all. Im worried that one day, I might get hurt in that part and I wont be able to breath because I hope to be very physically active. I also fart alot and I think I have minor anxiety.When I burp I also feel a little better. But I posted this in the Respiratory section because I believe it might be my lung. I also get some chest pains like 2 times a week. I went to my doctor and did a regular check up and he said everything is OK. Please HELP! Im very worried and would like to know this! ALSO, i had many stomach bugs when I was little... THANKS