Had a brain MRI shows small cyst neuro not concerned. Could it be ms? Cyst on brain! Concerns me

Cyst. Most likely the cyst is an arachoid cyst of congenital origin, and is unlikely to be of any clinical concern or significance. One solitary cyst as described is not a sign of MS or infection, or cancer, and should be best regarded as a coincidental finding.
Not MS. There are a variety of normal variants/benign cystic structures in the brain. Please discuss your diagnosis with your doc (neurologist). Please make sure your MRI was performed on a scanner accredited by the american college of radiology, performed by registered technologists and interpreted by a qualified, board certified radiologist (a doctor with 5-6 years of training after medical school!).