Welcome
We dont know what the download was either. It could have been an update for some software that you have installed that does not come through the Windows Update.
That first update, the Windows update seems to be the source of various installation abnomalies. I think that it had to be installed, in your case, by clicking on the notification button. Others have had loop problems, I had a surprising shut down, and, on reboot, a notice that Windows was updating. I would not be too concerned.
Run a full anti virus scan
Download and run a full scan with Malwarebytes and run an SFC. If everything is ok, just go out and enjoy your computer. http://www.vistax64.com/tutorials/66978-system-files-sfc-command.html