Some female hogs are out during the day, but usually busy nest building and probably early in the morning. Equally, the hog could be out during the day because it’s unwell.
The best thing you can do is to ring BHPS 01584 890801 to find the contact details of your nearest hog carers and give them a ring and explain things in more detail – and take their advice. Hogs, being wild animals do not want other animals (including humans) to know if they are unwell or not so are good at covering it up. A hog can be very unwell before it shows any outward signs that it is. Please don’t delay – better to be safe than sorry.