Journalist Jennifer Brea couldn’t get any doctor to explain why all her systems seemed to be collapsing. She used the Internet to diagnose her own disease, Myalgic Encephalomyelitis, better known as chronic fatigue syndrome. Her documentary, “Unrest,” starts out with shots of the University Medical Center at Princeton in Plainsboro. shows on WHYY and WNET at 10 a.m. tonight, January 8. It premiered at the Garden Theater with her husband, Princeton Politics professor Omar Wasow and Imani Perry doing the commentary.