Congratulations on your new baby!
Grass hay and pellets and alfalfa hay is what the House Rabbit Society recommends for young buns. The pellets should preferably be alfalfa based. Alfaalfa has lots of protein and calcium, which is why it’s good for young, growing buns but not for adult buns.
Greens can be introduced around week 12 (3 months), if the bun’s tummy is in good order. It’s the tummy that’s the most sensitive part of the young rabbit, and this is why greens shouldn’t be introduced until the bun has developped a somewhat diversified and sturdy gut microbiota. Hay is the best way to a good GI microbiota. If the bun has had greens while it was still with the mother and siblings, you can of course keep feeding greens.
The House Rabbit Society has lots of good info about diet and suitable greens: http://rabbit.org/faq-diet/
If you happen to have a picture or two of your buns, we wouldn’t mind if you were to post them… =D =D =D