I had the same experience. My first 5 or so dives, I was burning through air like crazy. I also had some pretty serious underwater-anxiety that I was dealing wi

I had the same experience. My first 5 or so dives, I was burning through air like crazy. I also had some pretty serious underwater-anxiety that I was dealing with. I spent some time just hanging out underwater without scuba gear, basically doing ~30 second underwater meditation to help the anxiety go away and to practice controlling my breathing, and my air consumption went way down, plus diving is way more fun when you're super relaxed and just moving around using the most minimal motions to propel yourself.