Welcome to 3FC and congrats on making the decision to lose the extra weight.
Gaining 30lbs in a month would require some SERIOUS overeating. I do hope all is well with your blood tests.
50lbs in three months is an extremely ambitious goal, especially considering how (relatively) small you are already. You'll find that 3FC isn't terribly supportive of crash diets, because the vast majority (if not all) are unhealthy and they don't offer any long term success. Most of us are looking to make a lifestyle change, not be on a diet, even if we are using a meal plan or specific program.
That said, there are a bunch of options available to you that offer healthy, sustainable weight loss. It will most likely take longer than three months, but you can definitely make a substantial dent in your weight by Christmas. There are support groups for calorie counting, weight watchers, ideal protein..just to name a few.

That is not to say you have to choose one of those plans to be effective, just that there are tons of options available to lose the weight and keep it off for good.
Hope to see you around the forum!