All products and services are listed under a specific class that correspond to all the different goods and services in the economy.
If you wish, you can register a trademark under one class and later use it for a product or service under a different class. However, you will need to file a new application with the PTO to legally register the use of the mark under the new class.
For example, if you register your logo for a beauty product (class 03) and later want to use the same logo to advertise beauty services (class 044), you will need to file a new application.
If the mark is already being used by another company under the same class, you will need legal assistance in order to assess your rights to use the mark under the new class.