A family of Microsoft relational database management systems designed for ease of use.
I think you made a great choice with Microsoft Access. In my opinion, it's still the best rapid application development tool available for building Windows database applications. It's easy to get started with, incredibly powerful, and there's a huge amount of free training, documentation, and community support available online.
It's perfect for a small business, and one of Access's biggest strengths is that it can grow with you. If your business expands, you can continue using Access as the front end while moving your data to a more robust back end like SQL Server without having to throw away the application you've already built.
Also, don't overlook the free Microsoft Access Runtime. If you eventually have multiple employees using your database, they don't all need to purchase Access. Only the person or people developing and maintaining the database need the full version. Everyone else can use the free Runtime edition to run your application, which can save a lot of money.
Good luck with your new business. I hope Access serves you as well as it has served me over the years.