https://www.google.com/search?q=lower+back+cobra+stretch&espv=2&biw=1252&bih=749&tbm=isch&imgil=PW_fBpG-g-rxPM%253A%253BM9FNmGdx8AfoPM%253Bhttp%25253A%25252F%25252Fhealth.howstuffworks.com%25252Fwellness%25252Fdiet-fitness%25252Fexercise%25252Ftotal-body-stretches6.htm&source=iu&pf=m&fir=PW_fBpG-g-rxPM%253A%252CM9FNmGdx8AfoPM%252C_&usg=__H_Llx1BaiDUxCAvWpe7-e_-b38I%3D&ved=0CCcQyjc&ei=RncZVZXUGNbkoATd9oKwAg#imgrc=PW_fBpG-g-rxPM%253A%3BM9FNmGdx8AfoPM%3Bhttp%253A%252F%252Fs.hswstatic.com%252Fgif%252Ftotal-body-stretches-abdominal-stretch-2.jpg%3Bhttp%253A%252F%252Fhealth.howstuffworks.com%252Fwellness%252Fdiet-fitness%252Fexercise%252Ftotal-body-stretches6.htm%3B400%3B271

Do some semblance of this even if you are too stiff to raise up to rest on your elbows. Or just lay on your belly like that but prop a pillow or two under your chest. If it really hurts to do this don't do it but it is OK if it feels a little uncomfortable and stiff. Do this often and don't sit for very long at all. When you do sit, don't do it without a GOOD lumbar support like a rolled up towel or something pretty significant. This includes driving in your car (the worst for me). You need to get that natural bend back in your spine which will in turn allow the disc to relax and not bulge into your nerve.