Your symptoms like body aches chills is basically related to fever but this fever will be related to either infection in body or the pain at your hip level. You have informed you have undergone for hip replacement surgery in march, usually hip replacement surgery takes 1-2 month time to recover with the help of physiotherapy rehabilitation program and post one month it is not supposed to be a painful condition. For you it s already 1 month over and still you are in too much of pain so I suggest take one xray of your operated hip joint and check with your orthopadic doctor for infection or healing issues. If everything is fine then you can use cold pack frequently at home to reduce inflammation and pain. We can also use alternately hot pack to increase blood circulation as well heailling process. If you have not followed physiotherapy rehabilitation after hip replacement I suggest to start following now and do regular exercises as well as the treatment as suggested by physiotherapist. Suppose if there is a problem in your hip x-ray like infection or healing issues you need to take enough of antibiotics along with calcium and vitamin d tablets for this your orthopadic doctor will guide you in detail. I am sure this will be helpful for you if you follow my suggestion properly. take care