drguy-
i bet you that you didn't fail. i walked out of the CS exam thinking dang it, i forgot to ask this, i forgot to write this in my differential, yada yada yada. hell there was one patient that i completely bombed, but at midnight last night i got the PASS (thank GOD). Anyways, i think its natural to feel like you failed. Now at my school, they tell us that many residencies won't rank you if you have not passed CS by the time when you have to do your rank order list (maybe that is just to scare us so that we get it over with earlier in 4th year). I think this may vary from each individual residency program, however it may not be a bad idea to look at what are the basic requirements for the schools you plan on ranking (more on the graduate medical education requirement page than on the EM residency program's website page).
I bet you kicked ass, and congrats on those interviews. It was only time before you got some good news.