One of the trickiest parts of owning a business is that there are no metrics outside of the ones you set. There is no one to tell you when you've done a good job -- and no one to tell you when you didn't quite meet the mark. So when a friend asks a question like, "How is business going?" it's hard to know just how to answer.
You could say business is going wonderfully: your sales are up exponentially from last year, and you are launching a few new products in the months to come. Or you could say that you didn't quite reach the lofty goals you set for yourself at the beginning of the year. And, because of that, you're beginning to question everything.
There are always two ways to see the glass: one half full and one half empty - and no one is going to tell us how we ought to be perceiving it. We have to decide that one all on our own.