Natural Pets

Hey, Please could someone advise before going to vets Tomorrow morning. My little dog was sick a couple of times and a loosish poo with tiny bit of blood on 48 hours ago. She seemed to get much better no more sick and a couple of nearly perfect poos but went off her food again today only eating tiny piece of chicken about 2 hours ago seemed back to normal if not clingy but now just this minute passed blood instead of poo. I'm besides myself. I did catch her trying to eat something on the lawn this afternoon but grabbed what looked like and old piece of kibble.