4 leads into a ceiling light and 1 has 2 reds and an earth?

Hello all,
Before I start let me point out that I am a complete novice at this electric thing, although I do have a fair amount of common sense...
Right then, I am trying to change a 3 way spot light fitting for a bog standard pendant. Having successfully dismantled the spot light I then tried to install the pendant. I have lots of diagrams and books...although the switch doesn't have a bit of red tape on it there is one black that looks like it has some paint on (am assuming this is the switch). I then notice that there are 4 flexes coming in through the hole - one of which has two reds and an earth. Where the hell is this one supposed to go and what does it do? Whatever I have done to it so far, I no longer have a working light...please help...
Thanks!

You also have another cable.

Is there another light which switches on and off with the same switch?

Thanks so much for your speedy reply - since its gone dark I have found that I now no longer 2 other lights upstairs...

The switch for this light only works the ceiling light - I have no idea whether there was a wall light or anything previously, but there is no evidence of one.

Is there a way to tell which of the two reds is the switched live? I have read advice about turning the power off and testing them with a meter whilst flicking the switch, but I don't really see how this works as there isn't any power...yes, I'm new to this so I'm sorry if I'm just being a bit thick.

Assuming that I just have an extra cable, can I double up on the neutral and loop connections?

I would assume the spare red and black is another feed to something else, so as you say connect it to loop and neutral.

As for the twin red, it doesn't really matter which way round you connect it, but if you look really closely you may see that the insulation on one of the red cores is solid red PVC, and the other is white PVC with a red coating.

This will allow you to match the ceiling rose and switch ends of the cable.

thank you so much for your quick help - all is now nice and bright in our house!

thank you again!

SuperEm said:

all is now nice and bright in our house!

Click to expand...

So, you gave yourself another shock, then?

hehehe

I even managed to get it fixed in the dark with a torch...I just glow a bit now...

thanks to all!