Driving on a flat tire is never a good idea! It’s totally understandable how much of a hassle it can be; not to mention the tow bill. For safety reasons, stop driving and have the tire repaired or replaced
During an inspection of the tire, you will know why the tire went flat, if it can be fixed or if the tire will need to be replaced.
What we know for sure is, if you drive on a flat tire, you WILL be buying a new tire. For safety reasons it’s best to buy tires in pairs. So you will probably end up buying 2 new tires instead of just one.