The dynamite has a blast radius which will damage the player if you get too close.
Are you standing next to the dynamite when it explodes or have you moved away?
Its ok, it didn't take me too long to figure it out and it could easily have been a real bug.
It's not unreasonable to be suspicious about bugs as there have been plenty of bugs that I needed to fix (some game breaking).
Glad you are enjoying it, make sure you play the latest version (v1.3) to avoid any of the bugs I have fixed.