Is there only so many reasons why i feel so exhausted and tired all the time? can't do anything physical without feeling shaky, weak, really fatigued docs and specialists still can't give me answers

Other issues?: Are you experiencing any major stressers in your life?. Have you been evaluated for depression? Stress and depression can have a major impact exhaustion and fatigue. Talk with your physician about being evaluated by a therapist.

No medical = good: If they actually say you are okay medically, that's a good thing. Clearly something is wrong and it's good it hasn't done physical harm yet. Have you thought about psychotherapy - if only to help you explore your behaviors for the culprit. Nutrition-diet? Sleep hygiene? Depression? Anxiety? Obsessive thoughts? Phobias? Also, a compassionate gym trainer/coach or yoga class might help build energy.

Are you under stress: If your doctor and the specialist have done complete evaluation with normal finding, how is your apetite and activity level. If both are okay. And you still have symptoms, seek a second opinion and have work for autoimmune disoders.