I Have L4-l5 Left Paracentral Herniated Disk 7mm With Ddd

I have l4-l5 left paracentral herniated disk 7mm with ddd and spinal stenosis through l3 to l5. Pain constant in back when walking, getting up, sitting down etc.moving awkwardly. Pain radiates down left leg. Occasionally severely, especially after walking 200m or more. I have to stop, sit, rest.
I've had NSAIDS for 2 months and undergone physio which made matters worse. I'm now booked for microdiscectomy, neurosurgeon remarked that due to evidence of progressive neurological deficits it would be better to have the surgery as soon as possible. Is this the normal in such cases?