I’ve been sick for over a year now not being able to do basic human things?

I’ve been sick for over a year now. I’m 29 female. Symptoms include: low vitamin d, underactive thyroid( normal now took levothyroxine),occasional heart palpitations, pale skin, swollen hands legs abdomen, dizzy spells, orthostatic hypotension patterns with symptoms, lung mucus production with cough, insomnia, constipation, pain in lower back shoulders hips legs. So far I’ve had a tilt table test(negative) heart ultrasound( negative) sleep study( negative) 24 hour urine collection with a cortisol level 4 points above normal. I went from functioning to now not being able to do basic human things like dishes and grocery shopping. So far my doctor just keeps telling me he’s not sure what’s causing all this.