Low carb crisis

Hi! So I am a teenage girl, and I recently discovered that I have a form of insulin resistance that causes me to break out when I eat foods that are high in carbs or sugar that raise my blood glucose level(this is a self-diagnosis, but I am almost positive that this is what causes my acne to flare up). I did low carb about two years ago to lose weight, but I had to increase my carb intake because I lost too much weight. However, when I increased my carb levels, my acne got steadily worse over the year that I ate carbs. So about two weeks ago, I started to do low carb again to try and clear my skin. My acne definitely looks so much better, but I am losing too much weight!! I am 5'2 and I try to keep my weight at 100 but I am slowly declining, and my current weight is about 95 pounds. My mom is tired of this struggle, and so am I. I do not know how to gain weight without increasing my carbs and looking like a pizza face again. Please, if you have any suggestions about what I should eat, let me know!! Thank you!!!