Get used to it, Michael. Weight-loss is erratic due to the many variables that affect out weight including fat loss, water loss or gain, muscle bulk, good bulk, metabolic rate, etc. Don't give up, just grind away at it and the time will pass quickly.
Average your weight-loss out over each month: if it's 4 Kg then you are doing well, as 1Kg per week is the medically accepted ceiling for sustainable weight loss.
For a person to to burn up 1 kilogram of fat they need to create a 37,000 kilojoule deficit - that's 5286 Kj daily.
So an average adult male would need to eat the equivalent of half his daily required energy to create that deficit - which is barely above the "starvation mode" threshold.
Now that your body has cease to panic from its initial shock of experiencing calorific restriction, it is probably now losing fat instead of muscle and water (as it would have during the first few weeks of weight-loss). Small regular losses are good losses.