Calendar events added show up on a different calendar

I am the Young Women's President, and use the public ward YW calendar in my ward.
Recently we added a private calendar just for the presidency, to keep track of assignments and when we're out of town.
I am listed as editor and viewer. The calendar shows up as active.
I close all other calendars leaving open only the private YW presidency calendar.
When I add an event to the private presidency calendar, the other (Public YW) calendar opens and the event only shows up on that calendar, not the one I added it to.
Curiously, each time this happens, the color of the Public YW calendar events change to brown.

When you create an event, there's a "select a calendar" field that needs to be set. It will default to something, and it may show a calendar that you have unchecked from the main page.