Something is definitely gone wrong with the install. It shouldn't take more than an hour to install windows 10, even on an older machine.
Your best bet will be to make contact with the official windows support team (assuming you have access to a working, internet connected machine).
This is the United Kingdom Microsoft support page:
https://support.microsoft.com/en-gb/contactus#
Once on that page, you click the "services & apps" tab and it'll put you directly into a web chat with a Microsoft support engineer who can talk you through your problem. It's a totally free service.
Hope they're able to help you out. Good luck