Any advice to help severe lower back pain?

Im taking care of my mom right now. She's 58 and has been suffering from severe lower back pain for about 2 weeks now. Before this she was in good health & we're still unsure of the cause. She doesnt have insurance so doctors & ER aren't really an option. She's in so much pain right now...she can't walk on her own. any advice?? plz help.