When you save your project, you don't really have a notification that you save it. I think that at the top of the screen with the menu bar, it will say Saved Project.
If your project has unsaved changes, then the name in the menu bar will have a "*" at the end.
But maybe something more noticeable.
@TheBenNorris It's worth noting that there's no asterisk on the Mac version (I think there used to be one). The only visual indicator now is that the icon changes slightly. When it's saved, it looks like this:
When there are unsaved changes, the icon "dims" slightly:
Also, if the window is maximized, the title bar goes away completely (at least on the Mac). Older versions (I forget how old) still had a title bar at the top when maximized, but a few years back when there were some major UI changes, this went away.