COULD A BIG CHANGE IN DIET CAUSE DIABETES? TAKING LIPRO DIET PILLS?

Ok, so i have decided i need to lose weight, i have tryed all kinds of diets and found one that works which is lipro diet pills, at the moment i am taking 1 lipro in the morning with 2 energy pills and 2 vitamin suppliments and a doctor stuarts slimming tea, but my question is that i used to eat loads of chocolate and have coffee with 6 sugars and now i dont have any sugar in slimming teas is it possible it couldve caused diabetes because at around 3-4pm i get really weak and shakey my arms and legs start shaking as well as going dizzy, all i eat is my tea at around 6, but because i have cut out all the sugar that my body is used to do i like need the sugar because i feel crap. Thanks a lot