Well PLOP! That sucks. What was it within the first hour that made you realize (just interested!)?
Anyway.....all is not lost. Those great grades you worked so hard for to get into nursing school are also good for a zillion other careers!
Here's what I do in these situations: I give myself a few days to mope and feel sorry for myself - there's no point trying to suppress those feelings, because they are real and genuine feelings. You're bound to feel disappointed, upset, frustrated with yourself, etc....so just feel them for a few days.
After a few crappy days of feeling like poo, gather yourself to re-focus on your new goals. If you are interested in medicine and helping others, have you considered dental hygiene? Medical assistant? Optometrist? EMT/Paramedic? (although you will have body fluids to deal with), forensics?, crime-scene investigation?, research?, counseling?, Therapist?, X-Ray technician?, Ultra-sound technician?, Respiratory therapist? Occupational therapist? Physical therapist? Lab technician?, pharmacy tech?, dentist?, pharmacist? Chiropractor, Herbalist? Massage therapist? EKG Technician? Esthetician?
There are so many options, you can transfer your grades and move on. Look at the positives of what you CAN do rather than what you CAN'T or DON'T WANT to. You're only 3 weeks in.....
That's a great thing - imagine if you were in the 4th year of a BSN before you came to this conclusion!