Hi graciepkg and welcome to NeuroTalk.
Foot tingling and twitching could be due to many different things. There is no symptoms exclusive to MS. A 1.5T is very capable of showing lesions.
Maybe your blood work will give you some answers. Just so you know, there is no blood test that will indicate MS as a possible cause. All blood work is used for ruling in/out other possible causes.
A couple of thoughts that may or may not be helpful
(1) you might consider seeing a podiatrist (foot Dr.)
(2) You might talk to your Dr. about having an x-ray and/or MRI of the Lumber spine (Lower back). This would not be for MS but possible back problems that could account for the foot tingling and twitching.
Take care.