Something strange happened...

Yesterday, I went to check the rank of one of my sites. The day before it had been at 18 for a somewhat competitive keyword.

  Before I started the rank checker, I thought to myself perhaps the site moved up in the rankings, as it had been on a slow but steady climb. I then started the rank checker...gave it a moment to scan through the data.

 I looked at the rank...Is it in the top 100? No. Okay, it must just be the google dance. I proceed to google, typed in "site: www.mysite.com";

 The homepage, nor any of the other pages weren't showing up. Only the backlinks were. I'm scared now; I look through all the results checking to see if perhaps it was on a different page - it's not. I try several variations of "site: http://mysite.com";, "site: mysite.com", "site: http://www.mysite.com";.

 It's not there! Sh*t! Have I been deindexed?? I start to search my weary little heart out about how to get my site reindexed. There's hardly any good information. I don't know what to do...I go to sleep thinking my site is dead =[

 Today, I wake up. I go to work, it sucks. Come home and check my email, not too much in my inbox today. I go to my google toolbar. I doubt nothing changed from the day before but I want to see what will happen. I type in "site: www.mysite.com";, and my site is there! The end.

If anyone can enlighten me, please do, as I am really confused.

P.S. Like my anti-climactic ending?