Why do i get sharp chest pains when i take a deep breath sometimes...?

Sometimes, like once or twice a month, i get a very acute chest pain, always on the left side or middle of my chest, when i take a deep breath, it goes away after ten minutes or so. Sometimes up to 20, but its EVERY breath that causes it for the duration. Its hard enough for me to take a full deep breath without this (i have to take a huge breath often because my lungs feel deprived) and with this pain it is impossible to take a deep breath. I don't know if its something normal or rare or whatever, but it sure is strange and no one I've asked about it has had anything like it. Any ideas on what it is or if it sounds like pneumothorax(i looked up this symptom on google this is what came up)