For the past week i've been getting the most unbearable stitch just below my ribcage on the right hand side. It only flares up when i'm attempting my sprints or my 1.5 mile run. It's so bad i have to stop after about 8 minutes in agony and i struggle to take deep breaths for a few minutes after this. I don't have any problems when i'm running distances at lower speeds only when i'm running fast, then for a few days after this i can feel it even when i walk places. I'm starting to worry now as i start basic in a weeks time and i can't manage to complete the 1.5 mile distance. Any help/advice would be great. Thanks.