OP - As much as many women laud the weight loss properties of breast feeding, there are also loads of women who actually keep on extra weight until they wean. Part of the body trying to make sure it has enough energy supplies.
You didn't mention if you were breastfeeding or not, but I thought I'd mention the possibility considering your babies age.
You haven't mentioned what you are trying - are you able to do a little exercise every day? I know you are probably shattered, but if you can even do a 20-30 minute video on youtube whilst baby is napping, then it will help kick start your metabolism, and will burn off a couple of extra calories.
Apparently exercise really helps your mood as well, even when you're tired, but I can't attest to that!!!
The only other thing would be to try and get your calories from things like pulses and veg and fruit, rather from foods high in fat. Even if they have similar calorie counts (which is really the most important), if your body is still in "fat conservation mode" it might help. Especially coupled with the exercise.