Hello, One Of My Friends Recently Discussed Some Health Problems

Hello, one of my friends recently discussed some health problems she has been dealing with for four years. She mentioned that since freshman year of high school, she has had swollen lymph nodes in her throat for seven months out of the whole year (this cycle has repeated for four years; she is a freshman at college now). She also mentioned that it becomes difficult to breathe while exercising or fast-walking. Her doctors do not believe she has asthma or exercise-induced asthma. Before freshman year, she weight-lifted and was in great shape, so this sudden lack of oxygen is rather odd to have. It also appears that she has poor circulation through her fingers at times because they slightly turn blue. She even has a condition (there is a term but I do not recall the name) where her toes turn purple and swell slightly as well. Her glucose levels greatly fluctuate, although she was never diagnosed as a diabetic. Finally, her knees have been bothering her. This symptom has been getting worse since freshmen year. She finds it painful to walk, run, kneel etc. But it has not bothered her to the point where she has a limp/gait. She can walk just fine, but she still feels an annoying pain, and she cannot kneel down. I have a hunch that this symptom has to do with her joint fluid? She seems to have a lot of unrelated issues, but I feel like they are interconnected in some way. I'm guessing there is some sort of circulatory problem...I just find it odd that she was perfectly fit and healthy...and then boom! All of these symptoms start to appear and get worse after 4 years. Her doctors believe that nothing is wrong with her, and that it's just "all in her head". But I don't believe that to be the case. Is there any disease or condition that would explain these symptoms?