Just keep a dairly journal so that if things progressively get worse you have everything documented. It will also help the doctor to figure out the puzzel.
Your on the ms board and alot of us have had symtems for more than 2 to 5 years before they figure it out and it takes alot of testing to get there. The cold ness in the legs and feet along with the tingeling could come for a pinched never in the L- spine.
At this time it's to early to say, Just document symptoms, date, what you did to releive it, how long the sinsation lasted. If you keep a record and things get worst you'll know. That's the best advice I think of at this point,