From top to bottom, we have
Stamina - If this becomes empty,
you don't die, you just become unable to struggle. It will fill with Purple as your mind begins to turn which doesn't seem to have any adverse effects afaik.
Gun Power - The more gun power you have, the further it shoots
Struggle Strength - The higher it is, the more effective your struggling is
Speed - The higher it is, the faster you run
Infestation - It works like a health bar but backwards. If it fills up completely, you're fully infested and it's game over.
Pregnant - If you become pregnant, this bar will start to fill, when it fills completely, the player character gives birth to a green worm.
Have fun out there.