It most certainly might be.

I don't know you situation, your weight, your stress levels... But make sure you are eating enough. Not because I am worrying that you are underweight, not at all - when overweight I need to make sure that I consume MORE calories because if I even try to put my body into starvation mode... Follow the rule of "less in/more out" that works for others - I not only didn't lose weight I would gain it unless I threw my system into extreme ketosis (which is very debatable if it is safe... And most don't want to or can't do it). If I missed something as small as a lunch while on a road trip I would without fail gain two pounds... So take the advice someone gave of downloading my fitness pal, or use calorie count in your browser BUT mainly to find you body's basal body rate (the amount of calories you supposedly burn simply existing, in a comatose state) and check that to the amount you are actually intaking. I was shorting myself about 800 calories a day without realizing it. After adding those calories in to my diet I lost weight.

Make sure you are at least eating your BBR and even if you don't start to see the scale drop see exactly what amount of calories you MAINTAIN at before you even worry about losing. Even if you do not have the problem I personally have, giving your body the amount of calories it needs to maintain it's weight will decrease it's stress and often people can then see pounds drop off when you start to healthily restrict calories.

Don't let the world make you feel bad about living with a different metabolic situation. I know that pain, both ways - needing to gain weight and needing to lose it... More food=More gains and Less food=More losses is not true for some of us. It took me years to fix my metabolism but I have, and it is worth trying something different! Eat happy :) lose safely :) consult a hormonal specialist if all else fails.