Brief Answer:
Neurological exam is needed.

Detailed Answer:
I read your question carefully and I understand your concern.

The symptoms you describe do require some attention. Memory loss is a subjective issue, meaning it should be evaluated through standartized tests. That is because often what seems like memory loss may be due to lack of concentration especially in the setting of issues like anxiety and depression. Also medications like the ones you take may affect concentration. For that reason before reaching to a conclusion of memory loss neuropsychological tests testing memory and other areas of cognition must be done to confirm there is true memory loss.

Regarding weakness of one arm and the contralateral foot that would go against threatening brain lesions like tumors or stroke. That is because they cause symptoms only on the limbs on one side when the brain is affected. So one localized lesion like stroke or tumor would not explain it. However it raises concerns about the possibility of neurological conditions with more than one lesion like multiple sclerosis, which might explain the weakness as well as the shaking you describe. That is a diagnosis which should be considered and excluded.

So the first step is a neurological exam, both to evaluate memory issue as well as to check for abnormal neurological signs like muscle weakness, increased reflexes, abnormal reflexes, coordination difficulties etc. If such neurological signs are found then brain imaging will be necessary. If exam is normal then issues may most probably be due to anxiety and imaging may not be necessary.

I remain at your disposal for other questions.

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