Take it slow, Sana - the slower you lose, the easier it is to keep the weight off - when we have weight problems we have to be careful of our intake for the rest of our lives - I read this at 25 and have been following it since - now 61 - and still a size 6.
Start a diary of what you do now, what you eat now - keep this diary as you go - not just what you do and how you eat but how you feel about everything. Don't go from eating - for example - 3000 calories per day to 1000 per day - that is a recipe for failure - just slowly change what you do and what you eat.
My hat is off to you - get some vitamin E oil or cocoa butter for your possible stretch marks - someone may know something better - but that's what I"ve always heard.
Hang in - let us know when you need support!!!!!!!!