What Causes Flu , Cold , Headaches , Body Aches , Nausea And Stomach Pains?

I moved to louisville ky about 9 months ago from cincinnati ohio. Weather climates being the same, I all of a sudden had severe allergies. Even Claritin D wont cure it. Now I've been sick with some sort of flu, cold, headaches, body aches, nausea, and stomach pains like 10 times in 9 months. I found some mold in the house we are renting and its black and in the shower and my sink. Could this be the cause? I am starting to get scared.