Traveller's Diarrhea For More Than A Week?

I was travelling in Turkey and on the third day I become very sick with vomitting and diarrhea. For the past week the vomitting has stopped, but I continue to have diarrhea. I'm very paranoid about parasites to begin with so I was wondering if there is any possibility of this? I think the quick onset suggests a bacterial infection, but I wanted to get some opinions.