At 5°C, your our iPad will have come to no harm whatsoever. Apple offers the following advice:
Use iOS and iPadOS devices where the ambient temperature is between 0º and 35º C (32º to 95º F). Low- or high-temperature conditions might cause your device to change its behavior to regulate its temperature. Using an iOS or iPadOS device in very hot conditions can permanently shorten battery life.
Store your device where the temperature is between -20º and 45º C (-4º to 113º F). Don’t leave your device in your car, because temperatures in parked cars can exceed this range.
If your device gets too warm or too cold, certain features might become temporarily disabled. In extreme conditions, your device might become temporarily disabled.
If your iPhone or iPad gets too hot or too cold - Apple Support