If you caught a real virus, at least it was God's will.
If you get YOURSELF injected, you can't even count on God's grace to see you through it. If you snapped, despaired, etc. you couldn't blame God, because it wasn't HIS idea for you to get the jab! It didn't fall from the sky and inject you spontaneously. YOU chose it, to run away from a hypothetical Cross. Your own fault.