OP said they changed the animation, not the animation frame, that might or might not be a problem. Further screenshots required
Pardon me, what is "OP" word mean ?
Change the "animation" or "animation frame" depends on your need and your sprite design
If you put it separately in different animation, then you should change animation (make the animation name is contain number, more easy to defined the variabel value of "life" or "heart"
If you only use 1 animation, but contain more than 1 frame, then you should change animation frame
Well there is a lot of method to do this..
you even can use separate sprite (destroy and create object on (X,y) or hide the sprite visibility)
All depends on your game design needs and your goal.. as long as prevent to use uneccesary alorigthm which need too much resources like "Every tick" cause the system counting every time...
Just my humble opinion :)