Persisten Infections, what is going on?

Persistent sickness!
The past year and a half i have literally been sick almost every month. i feel like i never get better. once i am almost over something (or so i think) i am sick with something else. colds, flu, bronchitis, infections, pneumonia, everything; i have had it.
I have always been one to catch every little virus going around all of my life, but this past year and a half it has gotten worse.

I am always freezing even if it is warm. i have night sweats that wake me up at night. i am ALWAYS sick. i am ALWAYS fatigued. i get headaches all the time and nothing helps any more. they are fullness and pressure in my head and neck (not a migraine). i am always tired or weak feeling and i get a full nights rest, i pride myself in making sure i get 7.5-8 hours of sleep. i get bruises out of nowhere and it takes a while for them to go away, and i literally find them randomly. like my tail bone will bruise if i sit on the ground for too long it is annoying; or even doing too many sit ups i bruise. i have really bad pain in my hips and knees, it my joints. but sometimes it feels like it is in my bones and the just ache and burn. certain bones are also tender and it hurts if they are touched too hard (even though it really isn't hard).
i also never have an appetite and thinking about eating makes me sick sometimes, but i know i need to eat so i try to keep my meal somewhat regular so i know i am getting my food in and not starving myself...even if it kills me i try to eat just a little something for meals.

I am a cheerleader competitively and i have been doing it for years and i am in really good shape, but lately i can't even make it through warm up without getting overly tired and out of breath and it is the same warm up i have been doing for 5 years. even going up and down the stairs wares me out now. i don't have asthma i have been checked.

i am a healthy person, i eat right i exercise regularly, and i don't really eat a lot of junk food or sweets mainly because i am never hungry and i am not super big on it.

i take vitamins, i drink water (i don't really like soda maybe like once a month) and i am not a big juice person, i water down all my juices.

i don't know what is wrong i am just tired of always being sick and tired and it is really starting to take a toll on my every day life

i have a hard time going to classes because i am always sick but i force myself to go, same thing with work.

please let me know! i am going and getting a physical exam with lab work on dec. 14th but i just want to know what you think too?