Can you gain muscle with a diet of only 90 grams of protien a day?

I'm a 13 year old boy, 6'2, and I have a rather "scrawny appearance", if you will. For the past nine months I've been going to a gym with a personal trainer two to three times a week, and my measurements barely changed. My diet on average consists of about 90-100 grams of protien a day, and I'm beginning to question if that's an adequate amount. My trainer told me that I should eat about 1.5 times my body weight, which is about 220 grams of protien a day, and I simply don't have enough food to make up for that amount. I also used to be dehydrated for the first 8 months of my training because I used to neglect my "daily water intake". Could dehydration be the problem, or not enough protien? Will 90 grams of protien daily ever make atleast some subtle changes, now that I'm more hydrated?