I think that starting a new game would have fixed this, but I didn't try.
Instead, I loaded the game I had started during the 60min time trial. Oddly, it started on a new character, but it was fine and I didn't have the bug anymore.
Funny thing, I found someone in my game, myself. I was just there standing next to a unlit fire and some bamboo chest i made in that old game. After a while, I decided to kill my old self, and it gave me all my old items. I left them since...