I'm very frustrated. I had a busted side light (it was taking in water) and my parents bought me a new one for my birthday, but fitted it and nothing no light, didn't work!! What else could it be?

Secondly. Started the car the other day while holding both the electric window switches down, now neither window works, (they were fine no problems up to then).
I've checked the engine fuse box window fuse, it's fine and the mirrors still work so it can't be the in car fuse box.
Volvo told me it was probibaly the control switches as it's a common problem. So i bought a new switch panel and nothing still doesn't work.
There is no power to the switches as they do not light up.
What should i do? Anyone had a similar problem?