Lumbar Puncture

I had my lumbar puncture on Friday. I had to be punctured three times to get enough fluid out for the tests. The doctor said he only got 3 cc's out of the first puncture and it stopped flowing. On the second puncture the numbing medicine wore off and I felt the needle going in. Not sure if that one produced any fluid. The third puncture, lower than the first two, produced the rest of the fluid needed for the tests. This third puncture was the most painful and I heard the doctor call for a 2 1/2 inch long needle. Can anyone tell me why the doctor was unable to get enough fluid out of my spine and does this mean anything? Thank God the doctor was very good, nice, and used a very small needle. Anyway, being tested for MS and was wondering if a lack of spinal fluid means anything to MS or another condition?? Thank you for the help in advance.