well i've been doing a bit of reading and i came across the cic website for lower skill workes so u fall in that category of C & D and in the FAQ sections it says u can apply to have ur permit extended with the same employer for another 2 yrs so i dont think u have to return to ur home country
here is the link i got my info from
http://www.cic.gc.ca/english/information/faq/work/low-skill-faq06.asp copy and paste it in ur address bar