As I've gotten older I've noticed when my estrogen levels are higher (especially when I increase my HCG doses) I become more moody and lethargic. When I take an AI I notice almost immediately a great increase in energy and better moods, less stressed, less headaches. I wonder if the lethargy is due to slowing down of metabolic functioning or liver stress or what. All I know is when my estrogen is lower I have much more energy. I take plenty of liver support (TUDCA), drink a gallon of H20 a day, just a weird phenomenon. HCG really raises my estrogen through the roof.