Norton is not activated after refreshing computer

Hello, I've been having major problems since I refreshed my computer. Just a few days ago, I believe I got a viruis which made "update your video player" pop-ups appear constantly. This also affected the strength of my internet connection, as it was very inconsistent and would never load anything completely. I purchased Norton Internet Security just a couple of weeks prior, so I did all the scans but it never found anything. Desperate to fix the state of my P.C., I refreshed my laptop (I have Windows 8) without deleting files. I thought this would retain my Norton product,but after it refreshed I lost my subscription.

 

I looked around the internet and many said if you sign in on Norton, you are able to re-download your product. So I signed in, but it said my Norton Internet Secruity was only downloaded today in trial mode. I tried activating it with my download key again, but it said it was invalid. 

 

I really need help on this. I don't think it's fair to purchase another copy of Norton full price just for another key code.