The worst feeling is doing a test or essay, feeling proud about how you did once you finished, then once you get it back you get a low score or fail, amirite?

Actually unrequited love wins the "Worst Feeling" award.

Sauce: http://www.news.wisc.edu/8271
http://www.nytimes.com/1993/02/...amp;amp;src=pm

I'd say the one you describe ranks 4,985th in the top 10,000 list of Worst Feelings. Give or take a rank or 10.