Good Luck from me too! Like sfgiants said, it will hurt, but once you heal, you will be so much better without those bad parts in your body sucking the lifeblood outta ya! I can't give you an estimate of how long you'll be in - I too was a really sick puppy when I had mine done (many years ago).
One hint -- when you are offered the meds and need them, Take Them. The time they helped me the most was right before I was gonna go "walk", esp the first couple of days.
Also if you feel a cough or sneeze coming on, grab a pillow and press it in against your belly. It really does help. Extra pillows on the bed are nice to stick here and there -- under your knees or behind your back when laying on your side.. you'll figure that out.
Best of Luck to you and be sure to post and let us know how things are going as soon as you can. We all will be thinking about you!!
Diagnosed with CD in 1979, many resections and meds
Perm Ileostomy July 1984 at Cleveland Clinic
Disease free since surgery