Knots in my Gut

So...
This morning I was romping around the internet, looking at bunny sites, and found out something....
Bunnies shouldn't be introduced to lettuce at a young age....you should wait until they're 6 months old or so....
But it didn't say why...
I immediately snatched out the lettuce I'd just given him - - - he's had lettuce this morning, last night and the night before last and he LOVES it....
So I'm talking to one of the managers at work and telling him the story and he's perplexed as to why lettuce is bad...
1/2 an hour later he comes back with an answer...
Apparently, their little digestive tracts are devoid of bacteria and the bacteria found in lettuce can actually KILL the bunny by making them toxic ! Even scarier is that the bunny can seem perfectly healthy one minute and just keel over the next ! ! ! ! As they get older, the bunnies systems adapt to be able to handle vegetation.
Needless to say, I'm completely freaked out now.
Granted, this article was referring to bunnies 2-4 weeks old and my bunny is 5-6 weeks old...but STILL ! ! ! !
So I run out at lunch and buy all 3 "Bunny Handbooks" they have available at the bookstore (I really need to write a letter asking them to diversify and expand their companion animal section !).
Only one of the books even MENTIONS a feeding schedule for bunnies that refer to vegetation and the age at which it should be introduced ! ! ! !
This book also says that a bunny at 4-6 weeks of age should still be receiving milk from it's mother.....
And they recommend vegetation introduction at 12 weeks.....
So after frantically calling J to ask him to check in on the bunny when he gets home I start to think....what if my bunny is past the critical stage? I mean, maybe lettuce shouldn't be given to him yet, but maybe he'll be o.k.
I have a bad feeling the next couple of days are going to be nerve wracking....
I am SUCH a BAD bunny owner ! ! ! !
:(