Electrical motor noise with headlights

hi guys, this is pretty frustrating - my car was running fine before this. Today i decided to fix my mp3 player, so i took the headdeck out and re-soldered my faulty joints. No new wires, just the same ones. Then I attempted to replace my brakepads, with no luck. Then I refilled my oil, radiator water, and coolant water. This is all for a holiday with my girlfriend in two days.

So i turn on the ignition. Funny, cd players working, but cigarette lighter lights dont. I check the fuse, it's blown. Turn the ignition on, this time cigarette lighter lights work, cd player doesn't. Now i've got this weird wire in my fuse box. It runs from my steering collum down into my fuse box, and it's connected to the headlight fuse. When I jiggled it, my cd player came back on. HOrray. Now i have everything working, so I start the car. Still fine, no dramas.

Then, being close to dark I flip the lids up (headlights on) and suddenly there's this awful electrical screach. It starts high pitched, and over 15-20 seconds lowers its tone until it dies. I kill the engine, and check my headlights with no ignition. They flip up fine, nothings caught in them. Then try with ignition on (not engine) and suddendly there's that noise again. Once it calms down, every five seconds it jumps my voltmeter up a few volts for 4 seconds, then returns it to the normal level. This is accompanied my a high pitched wine.

So my problem is, what might have caused this, and what might it be? It sounds like it's coming from the alternator, or radiator.. pretty much the middle near the airbox. It's very electrical.. sounds like something not functioning properly.. like it's stuck or jammed. The car runs fine without the headlamps on. Once they are on, it kills the stereo, high beams, and headlights intermittantly. I'm worried, I'm supposed to take my gf away in two days, please help, anyone think this sounds familiar?