Headlights went out

Went down a dirt road got back on main road made a right turn and the headlights started flickering to a low dimming flash then went back to normal. Then made another right turn into driveway and they started to flicker like they were going out. Parked truck came back out to start and the truck and the lights will not turn on but the flood lights work and turn signals work, brake lights work, tail lights work but not the headlights.