Today the challenges that you face are more mental than physical. You'll have to know what is right for you and stick to your plans. A good thing for you to remember is that you do have the strength to stay committed to what you want. You have a huge amount of strength inside of you, although you might have to go deep in order to find it! Time is on your side, so there is no need to push yourself too hard. Just take it slow, and you will make it!
