Have you checked your measurements? Sometimes the scale is slow to show results that you see though other measures. I also find I don't lose weight gradually but instead, drop several pounds at once, so weekly weigh-ins are not very telling for me.
How are you measuring calories burned through exercise? Sometimes your estimates using this website or what the cardio machines at the gym tell you can be overly optimistic.
Are you making sure your portion sizes are accurate? Measuring and weighing things?
Over the course of the week, overestimating how much you burn and underestimating how much you eat can cause yoru deficits to evaporate.
What about water intake? Have you had less water or more sodium in the last 24 hrs? Do you have sore muscles? What about your stress levels, amount of sleep, or time of month? All of these can impact a weigh-in on any given day. A gallon of liquid weighs a whopping 8 pounds, so you can see how quickly a little extra water retention can add up.
Bottom line: Be patient, stick with it. Remember that a plateau is determined by multiple weeks without downward progress, not one! Use measures other than the scale to measure your progress and remember that your body doesn't lose weight in a straight line, so you shouldn't let one bad week take you off course.