Hi, I suffer from a lot of the symptoms you are experiencing, I suffer with GAD (general anxiety disorders) sometimes it's really severe.. I'm not saying you have the same disorder but it seems you are suffering from a form of anxiety... First of all you need to stop reading from Google etc, anxiety comes with fear, dread, worry and panic, the more you read, the more you worry, you begin to self diagnose and even develop more symptoms... Secondly try to relax, back pain and headaches etc can be caused by being tense and overthinking, for example if you have headache and you worry about it, focus on it, the pain may feel worse, so try to relax and take your mind off it, I know it's not easy, if we could control it we wouldn't be anxious... You are only 17 so your hormones are all over anyway, you are still developing and it can be tough for a lot of teenagers, don't label yourself just yet. Take control of your thoughts, after all it's your mind, what you think comes from you. I have recently been trying this, it's difficult but it works sometimes honestly. I argue with myself lol.. when you experience physical symptoms ask yourself, have I eaten? Have I slept enough? Things like that.. when you have feelings of dread, insecurities, thoughts that suppress you, try and look at it logically, think about it, does it make sense? Why am I thinking this? What will happen if I don't worry about it?... I know it's hard, and it takes time. You've had bad anxiety for four weeks... Why??.. tell yourself it's ok to feel down, it's normal. Another thing iv found is that sitting around, doing nothing makes physical symptoms worse, makes me more tired, going without food (even though I don't feel hungry) causes fatigue, dizziness, twitching, aches, I feel cold... Look at what triggers your symptoms, try and motivate yourself even when you feel like doing nothing, push yourself. Every step is progress, be proud of yourself, if you fail at something remember, you are human, humans make mistakes!! See your doctor and please stop reading about other illnesses, chances are your fine, you just need to care about you, about your physical and mental wellbeing, people who don't have anxiety don't see how you feel, it's impossible, only you can change how you feel... Take care and I hope you are feeling better soon... X