OMG! I have EXACTLY the same!!! Man I thought I was the only one, I'm 14 okay and I have been worrying like MAD... I've had the pressure headaches and everything! Heavy leg.. My left leg feels heavy but it has shooting pains up it, it doesn't stop me from doing normal everyday things but when I sit down and think about it it comes on even worse it's really uncomfortable, I also have it in my wrist have you? I have been to the hospital twice and they first said it was tension/stress, I went the second time and they said it is sinusitis and I'm now taking medicine. I'm still abit worried but knowing that I'm not the only one kinda helps haha
I also had my eyes tested at the opticians and everything was fine my doctor gave me penicillin and it's really helped but my leg and arm feels weird, optician can see of any things wrong and stuff. Sorry for the double comment haha noticed this was back in 2010 did you find out what it was?