You should wait til 6 weeks at least to diet properly, your body is recovering, and you are jus building your milk supply. Give yourself a break and enjoy your baby, get yourself into a nice routine with LO and your getting a bit more sleep and then think about losing weight!
At the moment your body will be running on empty, trying to recover from pregnancy, get itself back to normal and be running on less sleep and making milk for LO! Your hormones will be all over the place too so of course your hungry!
Don't let trying to lose weight stress you out and worry you, just enjoy your baby and take it slowly xxx