Multiple symptoms be related to one illness?

For most of my life I have felt like an outsider, the feeling as if there was something wrong with me. My doctors as a child said it was teen depression or that i was trying to get attention.For 20 years now i still feel this way and the doctors tell me that it is my thyroid. I have "hypothyroidism" so now i take a synthetic hormone to help with the disorder. Well mentally and emotionally it has gotten worse. The feeling of depression, fatigue, body aches, anxiety, paranoia, brain fog, lack of general happiness, forgetfulness, and aggression. I know this is not me, deep down i feel there is something bigger. A doctor suggested bi-polar, but i did not have enough signs to be diagnosed as such.I feel as if i am on the verge of loosing my mind 50% of the time and that's on a good day. My family history contains bi-polar, heart disease, diabetes, and several more mental issues. could i just be going nuts or have a form of autism like a friend suggested? I have heard that a form of autism can be ociated with the attack on the thyroid causing hypothyroidism. At this time i feel confused because every time i see any doctor they tell me that it is all in my head. Well yeah that's why i am there. I get shrugged off or told just to stay on my synthroid and i will be fine. well it's gotten so bad i can even do my school work, spend time with my kids, or function properly on most given days.My life has completely become a daily task to smile and just get through. it is effecting me so horribly i have trouble recalling, thinking Straight, multiple thoughts congesting, loosing focus and no doctor seems to even give me the time of day to find out what is wrong. my question is what kind of doctor should i see?