It sounds like everything has settled down rather than gone. I fed DD till 12mths and like you, I felt quite empty at times, she was still satisfied enough and definitely still getting milk. The leaking and in-convenient let downs (like when I was at the supermarket shopping ) stopped at around about the same age your DD3.
If you are super concerned, purchase some brewers yeast and put it on your cereal to help boost supply and keep up the water drinking, especially now you are in a warmer climent.