What is this?

Hi there...I have been experiencing a few symptoms but I don't want to cause a big deal. Lately, I have been feeling lightheadedness, nausea after workouts of any kind, dizziness, tiredness for long periods of time then immediately after, medium-length bursts of high energy. Also, random shooting pains in my chest mostly, but someitimes arms and legs, only once has this happened in my neck. I have headaches without notice any more, and barely usually get any headaches. It is difficult for me to fall asleep at nighttime, I need to use the Aromatherapy pillow spray from Bath and Body works and listen to calming music. Once I do fall asleep, I wake up suddenly sometimes feeling like I'm sweating, but when I try and wipe my forehead, there is nothing there. After that it takes about an hour to fall asleep again. I will get random twitch kind of things in the area  next to my kneecap, my neck, the space between my eyebrow and eyelid, my lip, and sometimes in my thigh. If you look at it, you can actually see the twitch, and I feel it too. Is this some kind of cancer or just another illness?

P.S. I'm a cheerleader if that has anything to do with it. Also I am a dancer. Both sports require hard core workouts and training sessions after and before practice. 2-3 hours of cheerleading 5-6 days a week, and approximately 4-5 hours of dance a day...almost every day. If not in a studio learning choreography, I am at home in my bedroom/studio practicing routines and working on technique.

[Londres70]

This doesn't like any type of cancer to me.  

I would recommend getting some basic bloodwork done first, especially iron levels and thyroid levels.