2006 Nissan Frontier turn signal blinks once

When I turn on my left turn signal, it blinks once, and stops. The dash indicator flashes once and stops, and the turn signal switch stays down. I also notice the backlight on my radio clock dims when I do this. Right turn signal works normally (no dim on radio). Hazard lights also blink once and stop. When I turn on my headlights, both left and right turn signals seem to work normally (and no clock backlight dim). The other day, my truck would also not start after driving to the store (no response at all with turn of key). I wiggled the wires on the battery and it started up fine (though indications the battery had been disconnected and reconnected). I'm not sure if these two are related or if it was just a coincidence.