Hello Sarah!
  I'm sorry to hear you feel so badly on pills. I can't say about Metermine personally, but you've said you've been taking duromine too. 
 Well, as far as I understand the worst thing is lack of energy and no weight loss effect so far? You must be disagree with me, but I think your diet is wrong. Because 
 it's not only about taking the pills and eating NOTHING AT ALL, on the contrary - you have to eat, only small portions, low-calorie healthy foods and 4-5 times throughout a day!
 I know, I know you will say I'm sick suggesting you to eat "that much", but trust me, it's not like this. Your body lost 6kg for the first week, true, it was water mostly.  
 But you should know that any diet pill only helps when: 
 1. You eat small meals 4-5 times a day (main+snacks) regularly at the same time every day!
 2. You exercise (gym, Zumba, jogging, yoga, fitness, etc.)
 3. Drink a lot of water (2-4L) 
 These are basic conditions for successful weight loss. Worked for me. No cheating, no sorry for yourself, just a strict concrete plan. Otherwise no pills will work.
 If you eat nothing, your body gets no energy, even though the pills should provide it. Remember this and good luck! 
 XOXO
 Kate
 
  P.S. Everybody is different and many other factors may prevent you from loosing weight. My best advise is to try this plan and maybe you will see the difference. Oh, and one more thing: once you've started to lose weight, meaning you're changing your lifestyle completely, than you should stick to it all the time. There is no way back!