Many people who have lower back pain get it initially by dislocating their sacroiliac joint (such as by improper lifting of a heavy object while leaning over too much and not bending their knees) and not via pinched nerves in their spinal column. If this is the case, there are easily performed corrective manipulations which can place the joint back into place within minutes, and there are no further problems (see
http://www.kalindra.com/rounds.pdf for a description of si-joint dysfunction and suggested corrective manipulations). If your joint is not dislocated, these manipulations are unlikely to make things worse, I don't believe.
If the problem is not corrected reasonably quickly, and the problem goes on undiagnosed for weeks and months it can develop into a condition called si-joint dysfunction, wherein ligaments in the joint become permanently stretched, muscles atrophy, nerves stretch, etc and the problem requires the services of physical therapy.
I know something about this because it happened to me (and then later on to my oldest sister). One thing that is disturbing about this is that the doctors seem to want to do a lot of extensive tests first over a period of months rather than trying corrective manipulations right away. This costs a lot more money (which goes to them), makes the condition much worse than it might have been, and causes a lot more pain over time for the patient.
If this post doesn't help you, sorry! However, I bet there are a LOT of people suffering needlessly that this post could help. My sister developed her problem, it appears, as a result of a hysterectomy. She suffered for 10 months, 4 doctors, over $10,000 in medical costs, and nothing they said was helping much (peripheral neuropathy, they said). It was my personal experience w/ SIJD that finally caused me to suggest to her that that might be her problem (I could kick myself for not having suggested it much earlier). I pulled on her legs in one of the suggested manipulations for about 5 minutes, and immediately she felt better in her legs and could walk better. So she told her PCP doctor this and demanded PT, and after several weeks (now), she is clearly on the mend (although it will still take time, since she lost a lot of muscle tone and flexibility).
Readers, PLEASE remember this: Low back pain (hips or below) is often due to si-joint dysfunction!!!!