I am 12 and asthma does not run in my family.

I bet you're wondering what to do. 

Based on what you describe here, I highly recommend you tell an adult right away and have that person either call your doctor or take you to the emergency room.  Trust me, there is some excellent medicine that will help you catch your breath fast. 

Now, I cannot say whether or not you have asthma, but the symptoms you describe

do sound like asthma symptoms.  Asthma can cause the air passages in your lungs to constrict, and this will cause the symptoms you describe.  And, even though no one in your family has asthma, one of your parents may still carry the asthma gene.

Definitely, you need to see a doctor right away.  A doctor can also tell you why you are feeling this way, and if you have asthma.

Let us know what you decide to do and how things turn out.  And definitely feel free to ask any questions you think of. 

oops, that was me who commented above.

thank you, i might be going to a+e out of hours tonight...

turned out it was just a chest infection!