Sorry about your loss, RIP Cookie. What you described sounds like distemper:
http://www.marvistavet.com/html/body_canine_distemper.html

Take your beagle for a checkup just in case, but chances are she's fine if she's had the full set of vaccs. Distemper virus doesn't survive too well outside of the host body but still best to disinfect your house (with diluted bleach).