What Causes Severe Pain In Lower Buttocks After An Injury?

Hi, I am 49 years old.i had a bad fall last October 2014.MRI shows that i have a Disc desiccation and annular tear/fissure,L4/5 and L5/S1.Straightened lumbar spine,Diffuse disc bulge,L3/4,L4/5 and L5/S1 causing mild thecal sac indentation and mild bilateral neural foramina narrowing.Please help me what to do.I m suffering pain at the lower part of my butt whenever i am sitting and i have lots of sleepless nights already because i am afraid of what is happening to me.Please answer me.