Thanks a lot for the feedback, very valuable!
I took a look at the code and I (the programmer) fucked up. Was messing with the energy + stamina + fatness relationship and commented out the frame delta calculation while doing so, and never added it back before releasing the game! It's in a comment right next to where it should be... Unfortunately I only had time to test it on 60hz display (my laptop is 120hz) so never caught it myself...
My wife thanks you for appreciating her art she threw together in haste!
Regarding lack of feedback, you're absolutely right, could have been done better... The corn ultimately gets generated automatically based on the covered distance in your run, but that's not clear at all. Also, the mud patches are supposed to slow down the player, but never got it to work properly and hence didn't make it to the final release :(
And thanks for the number checking, amateur mistake made because of stress.
Overall, thanks a lot taking the time to give us some honest feedback, very helpful as it was both of ours first game.