Back pain

Back pain today...pretty bad.  I had another MRI, the third and last in 4 days.  Laying still on that darn machine is not helping lower back pain...They were behind at the hospital and I ended up waiting 1:30 before it was my turn.  I was looking at the clock thinking my time at the gym was going down the toilet and sure enough by the time I got out of the hospital it was time to go pick up my son at preschool.  Today was supposed to be a cross training day including weights and stretching...I hate missing workouts...this is week 2 of my training plan for the half but it is also supposed to be taper for my 10k....so with back pain maybe better to use today as rest day instead of Friday...
I have another day of waiting before getting the results of my MRIs...brain, c-spine and l-spine.  Wednesday finally I will have some answers...well I hope!  I want the good Dr to say: "You do NOT have MS"..yep that is the reason for the brain MRI...a little scary to see these letters in the Dx section of the order.  Also whatever the reason for my health issues..numbness being the one that sent me to the neurologist I hope it will not affect my running...