I was in a car accident a few years ago. Since that time after several weeks of phy therapy, I still had this issue of cracking my back excessively (several time concecutively and all day long). At first cracking it would relieve the pain and pressure but now I get no relief at all from the pain. The physician I saw for this injury told me I was getting old and to expect pains and "popping" bones. But this just doesn't feel right.

Our backs where never made for it to be cracked. Just be careful- cracking your back is 100% dangerous

Each time you crack your back as you put it sets your spine up for arthritis. For instance a person likes to crack their knuckles on their hands a lot. When they get older arthritis will happily make a home in the knuckles. If you are not getting any relief from cracking your back now, I would highly suggest that you stop this practice as it will lead to an arthritic condition later on.