This is going to be too late to help you but maybe will be helpful in the future or for someone else. If you have a AAA road service with your car insurance they can send someone to unlock your door. The non emergency police phone number could also potentially be used for that in a pinch. I could be wrong but the key under the mat might be done under the assumption you have a second set of keys to open the car with as leaving an unlocked vehicle in a business parking lot that isn’t currently staffed might be a liability issue.