Sharp pains in chest area

Hi, I'm 15 and every now and then experience severe pains in my chest/ribs area. It doesn't happen that often, maybe few times a day like 3-5 times a week. But it does hurt pretty bad, and I can't take another breathe without it hurting till the pain goes away. The pain only lasts like 5seconds, sometimes maybe 10. I think paybe my lungs are rubbing against my ribcage because I am kind of underweight, but I wouldn't know it's just a guess. I was born with symptomns of ashma and never had an attack or an inhaler though. I do have poor breathing though from my dad's secondhand smoke and tire easy when running long distances and swimming. Is this serious? or does anybody know why this is happening? Thanks for reading.