my headlights worked last week now when i pull the switch to turn them on nothing hasppens

On your vacuum lights you may have an open vacuum line that does not allow the lights to open. Your switch may be in need of replacement, or a vacuum hose has come off. Easy to check all the hoses. make sure they are attached. If you can, follow the hose from the lights, (both lights) to the vacuums source. since both do not rise, it is not a broken spring on a light box. Do the lights come on even when closed? Check the wiring from the switch to the relay that activates the vacuum to the lights. Ever since GM put in the vacuum light system, it has been a headache. They work 98% of the time very well and go years without issues. but when they go bad, it's very aggravating. If you never have changed the vacuum hoses, it would not be a bad idea to do it. I'm on my third go-round on my 69 Vette.