Hey, thanks for all of your help.
i realised what my problem was.
i put my headphones into the front of my pc,
NOT in the actual speakers (just to see if it was my speakers or computer)
and i had sound.
then i tried putting the headphone cord into the speaker socket, no sound.
so i realised it was my speakers.
i looked at the back of my computer where the speaker thing was plugged in, and i had it in the wrong socket.
i put it in the right one and it worked
im such an idiot.
lol, but thanks anyway