Unless you have a heart condition, high blood pressure
or have ingested or inhaled something you shouldn't have, the chances of you having a heart attack
are too tiny to even consider. You could have pulled a muscle, have something pressing on a nerve or just slept funny on your left side. No, you shouldn't sit and wait for the chest pain
(you could be waiting 80 years!). Try taking a shower (it could loosen up those muscles), take a few deep breaths (relax) and ask your parents for some Motrin
. You should be fine in no time!