Hi Lmurray,
First of all, welcome to our board and our madness!!

I dont want to be the one to tell you this, but Im 40, at age 39, I woke up one morning thinking that I slept on my hand wrong. Numbness, tingling and pain went from my finger tips to my wrist. I dealt with it for 3 days, and then it seemed worse. IT didnt go away. The following day, I had pain behind my eye and before lunch that day I was seeing double and hardly seeing at all out of the sides of my one eye...this led me to the emergency room where I was given a CT scan. That led to an abnormal result which sent me to a Neurologist- which led me to MRIs, evoked potential tests, Spinal Tap, more eye tests, and the long and the very short of it; MS. I got a second opinion from a highly respected MS doctor in the area (my Neuro actually called and got me the appointment, even he was stumped that a dx could come within a week) and that MS specialist confirmed what I already knew. I had MS.
Your question, how long did it take for this to go away? Well, I also had a round of IV steroids, SoluMedrol, 1000 mgs a day for 5 days..within 2 days the eye pain stopped and the vision returned, the hand..well, it never got better. 9 months later, I am sittting here in pain with this hand. It never ever stops. Howevr, give me a bad hand vs. blindness, and Ill gratefully accept the bad hand. The steroids helped, but only on the eyes...
Now, I also started Rebif. I was warned that it could take up to 6 months to start working...and in the first 3 months, besides the horrible side effects it was causing, I had 3 more relapses....then, all the sudden, the side effects stopped, I started to feel like I had more energy and less exhuastion, and yet my hand never got better. I had an MRi after 7 months on the Rebif, and it appears to be working...no additional Legions ( I had over 50 to begin with) and nothing was active on the contrast...and overall, I feel great! Except for this darned hand, which still tingles, burns and sometimes goes completely numb (usually when Im trying to pull something out of the oven!). I too, was incredibly active, worked out everyday, Im a size 2 and weigh 106 lbs. I was in great shape when this hit...no one knows where it came from, or why. All I can tell you is the people here have been incredibly supportive, and getting involved in your local chapter of MS will also help. But, more than anything value your kids! I had planned to start trying the same week my symtoms started. I have now been told that there is no way at 40 that I can get pregnant (only healthy women can do that) and that I am going to be childless....its really disturbing to me, but honestly, I cant see chasing a toddler around the way I feel. ALthough the advice is probably right, its a hard thing to swallow!
Let us know if we can help you...be brave. It gets easier!
Nikki