High energy during weightloss


I’m trying to lose the last 8 pounds – my question is that I have felt tired and fog headed and shaky when I reduced my food intake too much. At this point I am in fact very good at eating less, experiencing hunger and all. I also know that I have to work on the fearful thought” I don’t have enough energy if I eat less.”
However, in the past I have followed the “mimick fast” by Dr. Prolon with great success and realize it’s very easy for me to follow a protocol which I trust to give me energy. And it did.
But if I design my own meal that is healthy I feel I get very unsure if I get enough energy if I mostly eat veggies and reduce food intake enough so I still lose weight, which seems very difficult at this point. But I work a lot and need my brain 100%. Any ideas how to continue losing weight while keeping energy level high and finding a diet I can trust in that?