[33girl]

I think his worrying about the dork-ness and soon-ness is more about "wow, I just got my letters and here I am giving them away." The status/length of the boy-girl relationship is immaterial.

Until you're initiated and have had a while to KNOW what your letters really mean to you, I honestly would wait for at least a semester. Girls might think this is sweet as pie, but I can see guys (on a local and a national level) being somewhat offended.