Hi, I am having paresthesia in my left foot for 5 months... Is it MS?? I am 21 years old female. Few days ago I felt pain in both my legs

Highly doubtful. Would search for nerve pinching over left medial ankle, called tarsal tunnel syndrome. Other nerve issues should be considered also. MS means MULTIPLE, you have one focal issue at this point.
Nerve impingement. can be caused by being sandwiched between two spinal bones, pressed by a bulging. It can cause muscle spasm and back pain. Prevention treatment is always recommended. See interventional pain management specialist for definitive diagnosis and management. MS can be ruled out by MRI.