Strange Google Calendar Glitch with Multiple Calendars

I use Google Calendar for most everything I do. Since I have a number of different jobs I have a tendency to break things down into individual calendars. So I have my personal calendar events, my computer work, my piano schedule, Church. Each of these are in separate calendars within my Google Calendar account. So, usually when I go to add an item I get a drop down box in the dialog box that let's me choose which calendar to put the task in.

Today that vanished.

I don't know why and I don't know where. I worked with my calendar as normal today letting every new appointment go into my personal calendar which became quite annoying.

So, I started poking around the settings to see if something had changed. Nothing seemed different. I navigated to the list of calendars. I didn't want to share any of them. I clicked on the Church calendar to see the dialog to change settings related to that and didn't make a change. I clicked to create an appointment again and the drop down list was back!!! - Only two calendars to choose from - Church and personal.... hmmm

So I went back to the calendar settings page and clicked to "look" at the settings for each calendar and now I've got all the choices back.

That was strange....