Hello I Just Want To Know About My Knee I

Hello I just want to know about my knee I had a total knee replacement on my right knee March 31st 2015 and had a manipulation in May of 2015, now the doctor that did my surgery he retired at the end of June of 2015,,, this doctor I got now that did my manipulation. My knee is still bent and it not straight still having pain and stiffness in my knee, he want me to come into see him in March of this year.. I need help I feel depress about it all