Can a 26 year old get heart diease?

Yes. Acquired heart disease is uncommon at this age, but there are certain arrhythmias and myopathies that can present in young adulthood.
Yes. Yes it is possble. There are many forms of heart disease, including coronary artery disease, which is unlikely unless you had familial hypercholestrolemia, as well as valvular and other congenital or rheumatic heart disease, which a 26 year old could have.