Hi. I was diagnosed hypo 2 months ago. My symptoms were extreme tiredness, muscle fatigue and random aches and pains (I'm only 37). My TSH was just over 6.0. My Dr. put me on Synthroid (50mcg). Once I started taking it, I felt great for the first few weeks and then started feeling less great. I started to become very constipated which had never been a symptom for me before. I've also noticed that before my period I feel very drained and weak but during my period I feel hyper and my heart races. Has anyone developed additional symptoms after starting treatment? Have you noticed a change in how you felt based on your menstrual cycle?