Extra Easy Slimming world after weight watchers

Hi there I have just switched over from ww to sw and this is my second week and I haven't lost a lb!!! I'm sticking to the plan to the T and can't understand it, is it just the sudden change in diet from weight watchers to slimming world??? Am gonna stick with slimming world for another wk and if no good result next wk then I will have to go back to ww reluctantly!!! My sister, mother in law and friends are all doing great on sw but have been doing it for months now, dunno what's happening with me, though I do only have approx 7-10lb to lose! Please advise!!!!