Shoulder Rest Fails

So this past Sunday, I was asked to play in a recital given by one of my mentors. Aside from my nerves and cold fingers, it was going fairly well! I played better than I thought in the moment. However, I was not without my flaws. 
I was performing Mozart's Violin Concert No. 5 in A Major! I love this concerto! 
So I'm going through it and making most of my shifts. (I still have a lot to work on) But then I get to my couple measures of rest and think it's safe to lower my violin and turn the page. (I think it's only a total of 10-12 beats then right back in) I turn to the final two pages of the exposition (the ones I was most concerned about playing) and all of a sudden I hear a THUD!
............ I look down and see my shoulder rest just laying there. And believe you me, it came at the WORST possible moment in this concerto for me. I thought in my head one of those lovely four letter words which should not be said out loud in public but I was completely out of time and had to continue on to the next passage! 

So having to adjust ALL of my shifts and intonation to compensate for the lack of support under my instrument, I struggled may way through (giggling slightly with the occasional eye roll) to the end of the 1st movement. There was no time to pick the shoulder rest up and the show MUST go on! So I just kept going. No matter what, I had to keep going! Hopefully the other students learned from my mistake and will do the same if something befuddles them during a performance! 

Needless to say, I've switched shoulder rests, YET AGAIN... ;)