First off...congratulations on getting through your first day!!
I am very happy for you, and am sure that you will have a great returning day tomorrow as well.:)
As far as your incision site, have you had it checked out by your doctor? You will want to make sure it is dry, not red/inflamed, ect...
If no sign of infection is visible, it could be that you have adhesions in the developing scar tissue.
Ask your doctor about this possibility, as it can be broken up with massage to reduce the pain.
Have a great second day!!
S.C.