I Just Stopped Taking Oxicodone 2 Or 3 15mg Daily,

I just stopped taking oxicodone 2 or 3 15mg daily, usually 2, I was also taken gabepentin. I also took 2 50 mg tramadol. I stood one week ago, but have continued to take the tramadol. I have arthritis and knee issues. I am scared reading all this horror about tramadol. How and when should I stop. I never took more than the two prescribed