LOL! No worries; we've all done it I'm sure.
(Some of us more than once).
PCC's are now valid for 6 months, if you still live in that country. Much longer (apparently) if you're no longer in that country.
http://www.cic.gc.ca/english/information/security/police-cert/intro.asp
(Updated 23 Apr 2015)
For the country you currently live in, the police certificate must be issued no more than six months before you apply.
For countries where you have lived for six months or more, the police certificate must be issued after the last time you lived in that country.