I remember hearing that if you need both it’s best to get the hip done first. Everyone is different when it comes to recuperating and healing. But your knee has probably been exacerbated by the hip surgery. Doctors don’t seem to want to rush with CT scans. I’m not sure why. How about a visit to your primary care doctor while you’re waiting for your next appointment with the surgeon. Or call surgeon and request an earlier appointment due to knee pain. Best wishes.