Lost usb with wallet backups I was hoping someone would be able to help please?!!

I backed up my litecoin core wallet and neo wallet to my usb- today i took that usb out with me since I had other stuff on it too and needed to use it. I lost the usb like an idiot- is there a way to change the seed for my neo wallet and address for litecoin wallet so if someone finds my usb, they can't get into the wallets. I know I have backed them up on the USB but I am not sure what other info I have left on there.

I know I am an idiot- please help this idiot!!
If someone finds your USB and it has a full backup, they’ll be able to recreate your current wallets and steal all the funds. If you still have a working instance of those wallets, then you should immediately transfer all funds out of them and into new wallets. Do not use the original wallets to store funds ever again, create a brand new wallet (ie new seed) and use that from now on. 

Be careful with your backups, if someone stole your coins you would likely have no recourse at this point.