So, I got up this morning and saw that. Sixty-eight notifications. Checking my notifications only showed one notification, some thread with a name in an alphabet I didn't recognize, made by what seemed to be a bot. Checking it also reduced the number of 63. Refreshing the page reduced the number to 44, then to 20, then to 9, which appeared to be the real number. Then it also showed the rest of the notifications.
But this really confuses me. Anyone have an idea of what happened?