25 year old male with symptoms

Hello everyone, I am a 25 year old male that has been experiencing widespread twitching throughout my entire body for about a month. Head to toe. My grand mother had ALS at 60 but everyone in my family is saying it’s sporadic. Her mother did die of dementia at 88 and no other family member has been affected, as my grandma had 3 children that are all in their 50s and have no symptoms. I have a tremor in my left hand/arm and left shoulder is harder to hold up when laying down. I’ve noticed muscle loss in my left arm. All my joints are cracking and I have bad shoulder pain. I have been to two professionals that did neuro exams and everything came back perfectly normal. Neurologist kind of dismissed me saying my tremor was physiological and then diagnosed be BFS. Didn’t even look at the atrophy. Neuro didn’t order EMG and PCP actually advised me not to get an EMG. This did all start after the birth of my child where I went a few weeks extremely stressed with no sleep and after taking anxiety meds that messed me up. What still gets to me is the muscle difference between my left and right upper body. Seems as if I have split hand but my fingers are still strong. Neurologist straight up told me I’m sure this is not ALS, saw PCP for a second time and he said I do not think this is ALS and I think it’s all in your head. Should I be more concerned about this or should I trust the neurologist and Primary care doctor? Thank you