Pip review- reporting a change in circumstances

Hi. I was diagnosed with Kyphoscoliosis last year after years of lower back pain that was just dismissed by one Doctor. I saw a different one and he spotted it straight away and sent me for an x-ray. This confirmed his diagnosis. Although, not severe, I am in constant pain. It hurt sitting on a bus, a chair and I have to lay down at home to watch TV. My lower and upper back arecin absolute agony when standing in a queue, I'm constantly have to move around or sit in the middle of town. My concern is that I am already claiming PIP for EUPD. However, since then, I have also been diagnosed with Generalised Anxiety Disorder and Kyphoscoliosis. My review is in August and I'm too scared to add this additional information as it might start a new claim and then I'm rejected for everything. I am under a Psychologist and I'm due to see a Consultant at the pain Clinic on Friday. My life is so isolated apart from attending appointments. I'm really sorry for the long description of my conditions; I'm constantly tired and I'm so Anxious. The new Doctors I'm at now do not provide supporting letters. My old Doctor who picked up on this was really supportive. Thank you for reading and accepting me into the group!