some tremors in hands and arms at rest

okay so im really worried. ive been an anxious person my whole life but i never had physical symptoms. since february and the last few months ive been under a great deal of stress and even 3 panic attacks. it first started with chest pain and i collapsed at home only to get right back up. xrays showed nothing wrong with my lungs. ekg showed normal nothing wrong with my heart. then in march i started having body jerks(to note back in january i had them for a few weeks but went away completely) the jerks made me go see a doctor and psychiatrist who both said anxiety. for the most part the jerks have gone away. then in mid april my fingers started to jerk and my hands started to shake. i saw a neurologist and had a eeg done for epilepsy and it came back normal. i also did two blood tests came back normal. its almost going to be 3 months now in a week or two since i have these tremors. i tried lexapro and ativan and it helps with the anxiety but not the symptoms. i still have fatigue, sometime i feel weak but i am not because i can still perform tasks. i do get pains in shoulders, chest, knees, ankles, wrists, fingers that come and go. ive also noticed in certain situations or positions when my arms are at rest or my hands, they slightly shake. if i move them into another position it feels a bit uncomfortable and my hands and arms literally shake. they only are brief shakes/jerks and depending on the position they shake/jerk. most of the time my hands and arms dont shake at rest like right now, in bed, on a couch, their fine. but if their outstreched on a table or something in a certain position i get a tremors. its only been less then 3 months now but i have some action tremors, i do get postural tremors, and lately it seems resting tremors that come and go depending on the position. i am only 21 years old, a month from 22. everyone, the pschy, the doc, and the neuro are saying anixety. i begged all 3 for an mri or cat scan and all three keep saying i dont need it which is frustrating. i also get some tremors in my feet sometimes rarely and their barely noticable. also in my knees slight tremors that look more like a vibrating or contracting. is it possible i had PD all my life and after so much stress in the last couple of months the disease has been triggered and it is progressing kind of quickly? i have been reading so much about PD and diagnosing myself is a very bad idea but everyone is saying anxiety and i just dont see how because i dont feel anxious or nothing but tremors still occur. i get the internal shaking the pulsing muscles, sometimes my legs feel stiff but i can walk for miles, stand for hours with no problem. i am really worried that i have PD god forbid it scares the crap out of me but how can it be anxiety for so long? help, help, help. i feel like im losing it. i dont know what to do anymore or who to go too. whats happening to me, im only 21 is this possible???