False contractions making me sick?

So I am overdue and my body is slowing getting ready...lost my plug, some bloody show about four days ago. Now I am starting to have more braxton hicks or false contractions. The only thing I am worried about is that last nigh I had a lot of contractions that involved me getting chilled to the bone then ragging hot and very sick to my stomach. Has anyone else experienced this or know if this is common? I thought those symptoms were only in late stage of labor.