One of the things that will not realise to start with is that anything that gets damaged below the level of your injury may take longer to heal than normal, this is because your circulatory system is not working correctly. For instance if you stub your toe (you may not even feel it) and get a blister then it can take months to heal.
You must ensure you try to take good care of your skin, keeping an eye out for pressure sores as these are potentially really serious.