Thanks for your feedback! I think you are right about the memories part, maybe there should have been a HUD indicator for how many memories there are left.
Memories do not expire with time, but if you collide with them they disappear. I did not explain that well, oops!
When hit, you teleport to one memory, which destroys it, I'm not sure why all the memories disappear for you. It didn't happen with me when I just played it to check.
It would benefit to have a sound for coins, and coyote time, those should be easy for me to update the game with, thanks!