I Had Knee Replacement Surgery Exactly Two Weeks Ago As

I had knee replacement surgery exactly two weeks ago as an outpatient. I was given Percocet -5 325
mg tabs with instructions to take 1-2 every four hours. In an effort to stay ahead of the pain, I have taken 2 every four hours. Now I am out of the Percocet. After trying to get a call back from the surgeon, I found myself with many of the symptoms related to dependence. My question is: How long will it take to get this out of my system? Insomnia is the worst but the nausea and constipation is bad too. I havent had Percocet for four days.