Michelle, I was in ICU for 11 days after surgery. I think I spent a total of 19 days in the hospital. Most of that time I had pain, and for a good while afterwards, everytime the meds wore off.
But everyone is different.
You should speak to your doctor as soon as possible. Maybe you need a different med. (yeah, it's Saturday night. not so easy to call the doctor, is it?)
Back rubs help, and take your pain medicine on time, even if you are not hurting. It's hard to catch up once the pain gets ahead of you.
Of course, some pains can mean fluid buiding up around the heart which needs drained, or needs steroids to clear up.
If it gets worse, your doctor should have someone on call, but you won't get any Rx filled until tomorrow some time.