Rabbits are actually born with teeth, so they don't go through teething.
Rabbits will lick and nibble each other's fur as a sign ofaffection. So your bunny is grooming you and showingaffection for you.
You can give your bun some toys like paper towel rolls or applebranches. There are lots of different things you can giveyour buns to play with.
Just a quick note, are you 100% sure you bun is only 4 weeksold? Because rabbits should stay with mom till a minumum of 6weeks, but eight is much better. Watch your bunny verycarefully for tummy upsets as he/she will be very prone to upsettummies. Only feed pellets and lots of hay, no veggies untilbun is older (unless he/she was already getting them with mom).
--Dawn