Hello @MarkW0822 ,
Do you know how many columns of info you were importing? Generally for 100 contacts, even with quite a few columns, it should be an almost immediate upload.
Is it possible you were facing some connectivity issues? If you continue to run into weird lag for smaller list imports or while working elsewhere on our site, would you be able to try these connectivity troubleshooting steps, to see if they alleviate the issue?