Hi and Welcome to HealingWell, Sarah!
Yes, I think you should contact your Dr. and let them know this! I am not saying that you have a problem, for I'm not a Dr., however since it's been a full year from the last stress test and you are continuing with this problem and it's concerning you - it wouldn't hurt to have it done again. Have you had prior heart problems, or a family history of heart trouble? Do you have any current lung problems, such as asthma?
I would also ask to have an echocardiogram done. There is also another non invasive test that can be done - see the following link;
I hope this helps you out - my best wishes to you!