I had L5S1 ALIF fusion 10 days ago. All me back pain was home as soon as I woke up from surgery. Went home the next day & had only soreness. 5 days postop I developed severe pain in my butt and both legs. The back of my legs from my butt down to the bottom of my heels has a deep pain. It hurts to bend my leg (heel lifted to butt). Pain increases while standing. I was walking 1/2 mile twice a day & small walks every hour. Yesterday & today I just lay in bed with my legs propped up & walk the hallway each hour. What may be causing the new leg/buttock pain? Will it get better?