It's okay that some days, you're just not feeling positive about your business. It happens - the resilience you need to keep running a business is pretty intense.
The issue comes when you are struggling to get your optimism up for long periods of time - again, it might be that you are struggling with difficult market conditions, or you are using up all of your positivity on other areas of your life (perish the thought you do other things as well!)
But you know the difference between feeling particularly energetically low and that more persistent feeling that what you are doing is no longer the right thing. You can see the path has changed, but not where it is now going.
I have got you.
Never be worried about changing your path if the one you are currently on doesn't light your fire any more.