I found a bug where if you open the map while using stamina and then press the stamina button it will consume and then regenerate while the map is open, effectively, infinite stamina.
In other run I got infinite health, but I have no idea how.
Viewing post in Halls of the Pale Widow comments
I can actually provide a bit of insight towards the infinite health bug; I have noticed that when you drop down to zero HP, you don't immediately die, or at least that has occurred on pretty much every game I have played, if you were to pick up a healing item during that time it causes the bug to occur; my guess is that because the widow is supposed to kill you after tapping you an additional time after hitting zero HP, your HP value freezes to prevent underflow, and because you have picked up some healing your HP value increases but is never unfrozen, and as a result she can no longer kill you.