Fandango tickets and groupon?

So, I'm looking for discount tickets to the movies this weekend. I joined the theatre with my email address. Then I get a groupon discount ticket for $4 FOUR DOLLARS for a movie ticket. I need the tickets for Saturday tho' and it says expires today. Is that because I joined today? If I joined on Saturday would I get the same deal? I've never used Groupon so I don't know.