When you use your standard deviation for 1 hour to compute your swings for longer lengths of time, the results will be more accurate than when you only use it to estimate your swings for 1 hour. The reason is that in the long term, your results will closely resemble a normal or Gaussian distribution (bell curve), but in the short term this is not exactly the case.
For example, a true normal distribution has tails that go off to infinity and negative infinity. Since you can't actually win or lose infinity in 1 hour, the result is that the extra probability that would normally be in the tails of the curve get pushed in, making the tails thicker. This means that your swings for short periods of time are likely to be a little larger than what your standard deviation would suggest.
If your results were truly normal, your swings would lie within +/-1 standard deviation of your average 68% of the time, and within +/- 2 standard deviations 95% of the time.
Your average swing will be +/- 0.8 standard deviations.
Your median swing, which is the swing you exceed exactly half the time, will be +/- .67 standard deviations.
These estimates can give you a rough sense of how you are doing without a lot of calculations. Just remember that results in the short term are just crude estimates, and they are less reliable for reasons that have to do partly with statistics, and partly with your particular circumstances, such as being in a particularly wild game.