Seems like too much to me. I did try two different chiropractors when I was having back problems. The sessions always felt good, but didn't really help.
The only long-term relief I got from my back problem was when I went to a clinic that specializes in neck and back pain. They use exercise machines that isolate the muscles that need strengthening. Went twice a week for 6 or 8 weeks, and haven't had pain since!