Exercise Normally. Why Am I Losing All My Energy? Why Has Acne Vulgaris Returned?

Hi, I am a 26 years old female, I exercise regularly and am generally in great shape. I dont smoke and the most I will ever drink is an an occasional glass of wine. Recently, I began to get worried about my health. I normally exercise five times a week but suddenly I lost all my energy, my joints began hurting, I get severe muscle pain and otherwise feel constantly exhausted. I have recently graduated from university after a very intense exam period and I am not studying for another qualification, with only a month s holiday in between. I wonder if this may mean I am simply too exhausted. However, the symptoms are too severe for me to just put it down to tiredness. I think it s something else. I have very low blood pressure (always did) and I suspect my iron levels are down, since I quit eating red meat three months ago (I have a history of anemia ). I also often feel nauseous, especially when I get up and/or turn my head to the side. I just feel as if though I am breaking down. My acne vulgaris has also returned, despite two rounds of Roaccutane (last taken a year ago). I simply dont know what to think. Thank you.