do i have cancer?

ok i have alot of things going on i have nose bleeds alot, sometimes my top layer of skin feels like its bruised even a slight bump and im in pain but its not all the time, i also bruse really easy, i get head akes it will feel like a normal one and then i will get a sharp pain in my head randomly while i have it, i also get a sharp pain in my one side where my ribs are and i cand breath in or out and then when it passes i feel like i cant get a good deep breath,my joints are sore alot not just when the seasons are changing, i have gained a bit of weight really fast and it weird cuz my parents are very thin and we dont really have anyone overweight in our family, also i seen to catch every sickness that is around. i cant remember everything but thats most of it. please i dont know what is going on, what do you think? oh and im a 21 yr woman