Wow ! I'm impressed by the effort you put in this game for only a game jam scope !
With a little bit of polish it will actually be a really good game :
- Adding sounds feedbacks in fights will make it more enjoyable. Some particules effect will be cool too.
- Making the character actually walk from one fight to the other (on the map) will make the game feel more realistic.
- A little tutorial will not hurt to be honest ! Just to explain that enemies will get stronger if we heal and forward the time ?
Good job anyway ! You have a good prototype to work on :)