Heart disorder symptoms and conditions

started Zpak last week for a lingering sinus infection. I live in an area where the weather changes constantly. Two days after I finished the 5day Zpak I began experiencing horrible and flu-like symptoms and worse. I can hardly breathe out of my nose. Heavy chest congestion. Lots of diarrhea and even blood in the stool one day. Taste buds are gone. Here I am a week after finishing the Zpak feeling HORRIBLE. I'm afraid to go back to the doctor (uninsured) only to be prescribed something else that might bring on more side effects. Right now I'm taking Sudafed PE and hoping that kicks it. I've been on a Zpak before but NEVER had side effects like this. I don't wish this on anyone. and I'm wondering how long the Zpak stays in your system? It is possible to make you sicker? Seems so in my case and many others here.