2006 Kia Spectra Electrical issues after changing battery

My battery died and I put in a new one. Now, the radio, the dome light, the reading lights, the dashboard clock and the remote locks aren't working. Also, the right turn signal flashes in an irregular pattern. The last symptom is very strange. With the headlights on, the left turn signal flashes as if there is a loose connection (all the time) but with the headlights off and I turn on the left signal, it flashes like it's supposed to but my entire dashboard lighting flashes in time with the turn signal. I suspect there is a computer module issue but I have no idea. Any help would be appreciated.