Yeah, I think 4wo's generally sleep heaps. I think its usually around 1 - 1.5 hours 'recommended' awake time, but of course every baby is different and it is best and easiest to just go with your baby's needs.
As for what you should be 'doing' for your baby, good heavens, I don't think I had even come to terms with the fact that I had one at 4 weeks LOL!! You're doing awesomely, and soon enough it will feel natural to talk to your baby (I'm a really quiet person too, and one day I just found myself doing it...)
Eye contact is really important to a young baby, I believe. You can communicate so much love when you just look into each others' eyes. And that's all your baby wants - to be near you, to be loved by you, and looked after by you. They need that more than 'entertainment'. You're your baby's world, Haydies! You're doing brilliantly