where are my shared albums?

I just updated to Photos, and I can't find my shared albums anywhere. When I go to the "shared" pane it says "iCloud photo sharing. share photos and videos etc etc" with a "start sharing" button. If I click that button it asks me to create a new album. But I have at least 10 shared albums already, (including one with all the pix of my infant son- it had better not be lost!)- where are they???

And, if I click the "start sharing" button and go to create an album, it doesn't work. It asks me to made a title and choose someone to share with- then the window just disappears and nothing happens.

I've quit/restarted photos, turned photo sharing off then on again in the iCloud pane of system prefs, and rebooted the computer- still no luck. Help!!