It could be normal, but you can’t tell for sure if you don’t find any fleas or flea poop in the fur. Here’s an article from Medirabbit with pictures of how a typical flea infestation can manifest, warning though, there are nasty big pix of how the various fleas that can infesrt rabbits look too:
http://www.medirabbit.com/EN/Skin_diseases/Parasitic/fleas/Fleas.htm
You can use Advantage on rabbits, for fleas. You can use the kitten dose. This is an issue we always issue when external parasites are mentioned: Never use any compound containing Fipronil on a rabbit. It’s deadly toxic to rabbits but very commonly used on dogs and cats. It’s sold under many different brand names, for example Frontline and Sentry, so be observant.
Do you see any kind of dandruff or flakiness in his fur? Rabbits can have fur mites (often from their mother). Advantage would not cure that. For that you’ll need Revolution (selamectin) or ivermectin.
Here’s some info about flea treatment from the Sacramento House Rabbit Society, scroll down to “what about topical treatments”
http://www.allearssac.org/fleas.html
It’s always advisable to take a new bun to the vet for a check up. And, as Sarah also says, if you happen to be in Europe or Australia, there are vaccinations a bun absolutely should have, and that could be combined with a general health exam.