I had slight l5-s1 slip(6mm). I had pain that would go away with strengthening core and stretching. Physical therapist pressed really hard on my back. For a little while i felt no pain at all. Then intense sciatica set in. A lirrle later i got shaking in legs, and pain went away. They feel Like im tired, even though im not, and sometimes they feel like im carrying weight, which im not. Shaking happens whether laying down or standing up. I think it goes away when walking. Have you seen this before? Will strengthening core solve this.