Yeah, critical mode = game over. Just hit start and retry.
UNLESS (this is the ONLY WAY FOR IT TO NOT BE THE END):
-You have an enemy body party fully scratched nearby. Then have a person shoot and break the body part to get your shards back and get you going.
-Thus sometimes if you know you're going into critical soon, you can full scratch a body part before you do and then shoot it after you go in to get out.
But usually it just means you lost, so man up and retry.