I’d say him licking himself is a good sign. The rabbit mum typically leaves her kits to themselves for the largest part of the day, after wrapping them in a warming “cocoon” made of her own fur. She visits the kits once or twice per 24 hours to feed them for a few minutes. This works because rabbit milk is extremely fat (= very high in calories) and the fur wrapping is very warm.
That said, I dont know enough about baby buns to give proper advice. We have some info on care of oops litter babies in our Resources pages. (Scroll down to Pregnancy\babies -uh oh oops babies https://binkybunny.com/links-to-house-rabbit-resources/).
The BB forums prohibits discussions on intentional breeding, which means our members tend to not have the relevant experience with very young buns. The rabbit forums Rabbits Online has a whole section dedicated to rabbit breeding, pregnancy care and care of rabbit babies, and I think you’d get more relevant answers there: https://www.rabbitsonline.net/forums/the-rabbitry-and-show-room.20/