Knitting short rows on circ's??

[HelenaBeana824]

I am new to this, and making some wool pants for my son. Not using a pattern. I need to add some short rows in the "bum" of the pants to make room for his cloth diaper. Can I do this leaving it on the circular needles, or should I switch to DPN's?
This is the first project I have done on circs, I usually stick with DPN's.
Also my first time doing short rows, and I want to do them with the wrap.

Please help?!