My best guess:
@britmom5, it is close to a banned word. The explanation is pinned somewhere but I’m not sure where. And (as stargirl well knows) we have one living the backup plan and one the dream. Each has its positives - and the backup plan is decidedly better for the parents! 
Oops, posted same time as BlairParent!
Thank you! I do know how to spell, I think my fingers were flying faster than my brain!!
Your usage was correct. 
I feel fairly confident in my applications; not enough to be like “I’m so gonna get in everywhere!”, but just enough for me to not be shaking in my boots come March.
Worse comes to worse? I stay at my school, or if I feel the need arises, I apply to the Honors course at my local public high school 
The idiomatic phrase is “worst comes to worst” 
It depends
http://www.nytimes.com/2011/02/06/magazine/06FOB-onlanguage-t.html?_r=0
And according to Billy Joel, it’s “Worse comes to worst.”
I trust the Oxford Advanced Learner’s Dictionary more.
I never type the phrase. I just mumble it and hope people will give me the benefit of the doubt. 