Hello and welcome to the forum.
Typically and upgrade to Windows 10 maintains all users files and folder (C:\Users\UserName)
At the sign in screen do you see another user to select as a login option in the bottom left of the screen?
Is this Windows 10 Home or Pro?
Regardless you should be able to see all users on the computer by opening an admin command prompt.
Right click the start button and choose Command Prompt (Admin) and in the command prompt Window type
net user
hit enter
do you see the user account you are looking for listed among the user list?
There is only one user shown at the sign in screen (user 1). In the Windows 7 mode it used to show both users. The 10 screen only shows one (user 1).
I don't know if this is Home or Pro. It came up as a free conversion while in 7.
The net user window brings up an Administrator (user 1) , and a DefaultAccount (not user 2), and nothing listed under Guest.
How do I open the DefaultAccount to see if it is really user 2?