I bought this thing online that hooks to the top of my inhaler,,,it's called a doser. It tells me how many puffs I took that day,,,how many puffs I have left in the entire inhaler,,,keeps track of the date I started using it also. It was about 30 bucks but well worth it to me.
I was told that the inhaler will keep spraying,,,feel like you have stuff in it,,,even when you don't. The stuff your feeling when it's empty is the propellent. (did I spell that right?!)