Elecric light glows when I switch on another light even though its not been put on?

I have installed 2 down lights that change colour and taken the main feed from another light rose However when I switch the coloured Lights on the ordinary light which I have taken the main feed from the ordinary bulb glows Dimly any suggestion what i may have done wrong?I have connected the two coloured light wiring which is Twin and earth lighting cable to a 20 amp J Box I have put the two brown live together on one terminal in jBox and 2 blue neutral together on another terminal in the jBox the switch cable the brown has gone to the Brown terminal and the blue neutral gone to a seperate terminal where I have put the Brown from the Live feed and put a red tape on the Blue showing it Now a Live so in all there are 3 brown wires on the brown terminal three Blue on the neutral terminal a brown and Blue on the seperate terminal in the junction box any suggestions what I have done wrong ?Elecric light glows when I switch on another light even though its not been put on?Sounds like it's wired in series..