I think from the title of this that your hog is dead? The fact it was covered in bugs ( I assume you mean fly eggs/maggots ) means it was likely ill for a while.
It is unlikely the fireworks bothered it unduly as they are pretty tolerant of noises the more they come into our human habitats
Small hogs at this time of year are often in need of help. There is a number on this site for the BHPS helpline who will link you to a carer in future.
Meanwhile, hogs only need to be 450g in order to survive hibernation. The old advice of 600g is dated. Obviously the more weight a hog has the better it’s chances but it’s no guarantee it will survive hibernation. There are a lot of other factors involved.
Hogs of 400g plus that are active and healthy and coming to gardens for supplementary feeding do not need rescuing. It is far better and less stressful for the hog if it is just monitored.
Hope this helps
