Text by path - Wrong curve(?)

The other answers have identified how to flip the text.

Another thing to add - if you want to change the start point of the text on the curve, Command (Mac) / Control (Windows) click the small x on the curve and then drag it along the curve. You can drag that x away from the path and that could flip the text as well.

I replicated your problem and what you can do is using the type tool, click onto your text, like you're going to edit your text.  When you have the little flashing line icon in the text, hold down on Command if you're using a Mac, Control, I think if you're using Windows.  That will show a box around everything.  in there, you should see an X in there and a diamond shape,  the diamond shape will move the text and if you move up, it'll flip your text right side up.  Sorry if I am not using the right terminology.  It threw me off for a sec because I'm so used to moving text on a path in InDesign that I never used it in Photoshop,  but I was able get it to work in there.