I turn my air conditioning on when it get above 85 degrees. I cannot stand sweeting while I sleep.
The problem that I am having is that my first floor is freezing, while my second floor (where my bedroom is), it still extremely hot.
Or is there a way to redirect air from the first floor to the second?
It sounds like your problem is one of air circulation ("my first floor is freezing, while my second floor [is] extremely hot"). A much cheaper solution is to solve the air circulation problem by using fans, which will be much cheaper and effective than air conditioning. Remember, warm air will want to rise and cold air will want to sink. To start, you'll want to chase down any air leaks like innkeeper77 suggestion.
First, what are your night-time temps? If they are comfortable (say low 70s) the easiest solution may be to put a simple $20 box-fan in one of the upper windows set to push air *out*, and crack a window in the bottom floor. That will draw the cold air up through the house and into the bedrooms. This is what I did when I lived in Virginia and it worked very well, except when nighttime temps went into the 80s.
Another approach is to set up paths to have the air recirculate. If your home has good ductwork you can either use the recirculation fans (if they have them) to pull air from the top floors and deliver it to the bottom floor. Or you can set up a simple fan on the ducts to set up a convection cell. Placing a high-volume fan at the base of each staircase pointing up will help force the cold air up.