Well how bad does it bother you. I mean everyone experience gaps in memory. Medication, sickness like a cold, over tired, to list a very few can and will cause memory slips. If it is really bad, then I guess check it out. If it is an occassional slip, then you are stepping right along with everyone else you share space with.
Id hate to see you go in for tests, and for what ever reason loose your driver's licence when in fact there is nothing wrong other than normal daily things.
Sometimes we have to be very careful with what we really want to know. Heck, it could absolutely have nothing to do with MS - but a doctor on a mission may think or say otherwise...
Just be careful what you ask for..