My son in law is a chiro. It would depend on what your problem is. I do know for some problems it is important to continue to put the spine back in place several times because if it has been out for awhile the muscles will pull the spine back to the position they have been in and it takes several times to retrain them to stay where they should be.
It doesn't hurt and is a good idea to maybe get a second opinion. Just as a medical dr there are differant opinions.
When Ben does anything he always explains what the body is doing and what the procedure he uses does to fix the problem. He educates you as well as fixes you. so if your DR didn't tell you ask why so many visits and what they will do for you.
It is important as a patient to be knowledgable in all areas of your care.