More cactus question

I hacked of a few metres of cactus from a plant and im trying to determine if its pedro, it is long and cylyndrical like pedro, it had the same pedro flowers as the one i bought from the nursery, my doubt comes from the form of the plant, most pedro cactuses ive seen are one branch straight up, whereas this tree had many branches. More doubt comes from the fact that i cut mainly the ends of branches off and the green inner layer isnt as thick as the plant i bought from the nursery, Also In some parts it has 6 segment but in some parts it is 8 segmented... thnxs for any help

can you get access to a digital camera and post it up? it would make it a lot easier and more accurate.