I figured it out! I forgot I had changed the site settings a few days ago to prohibit registered users from accessing it while I edited it. Only admins / editors had permissions - so when I created the test user (who was neither an admin nor an editor), it wasn't granting access.

I wish the system gave some sort of notification though. When the page refreshes without an error warning or anything of the sort, it makes you think it's just malfunctioning.

Thank you. Will mark this as solved.