She is only five weeks old at the moment, don't rush her. It sounds like you have a good routine going during the day and for bedtime. Once she is alittle bigger to take on more food she will start to sleep longer. my little boy started sleeping longer when he was about 10 weeks old, i.e from 10.30 at night until 6.30-7am. He is now 5months and sleeps from 7pm-7am. I made sure he fed lots in the day. Stick to your routine and once her little stomach can take more food she will sleep longer. I took some ideas from the contented little baby book, but it is a little rigid for "normal" people who can't afford live in help. You will get there I promise.