Sounds like Pleurisy to me. Pleurisy is the painful inflammation of the membranes that surround your lungs. The cause can be a number of underlying conditions. I had a bout with bronchitis when I was 11 and developed Pleurisy and have had it ever since. They call it 'devils grip' and it feels like something wicked grabbing your lung in one spot like you describe.

Maybe if you fell to the ground and started bouncing around your mom would be convinced you need a doc visit...
then again, I've noticed you have a handful of ailments , so maybe she'd think you were crying wolf?
Good luck to you.