Honestly, I don't notice a difference in myself when I drink caffeine or when I don't. So it's not something I've ever worried about. I just avoid chamomile tea. I love it, could drink it all day...but it puts me to sleep.
I hadn't heard about avoiding herbal teas while pregnant. But it seems each week the list of what you should avoid changes, doesn't it? I went through a period where I drank nothing
but herbal teas, trying to find something that helped with morning sickness (there is supposed to be an herbal remedy for morning sickness out there, but I never could find one that didn't include chamomile). I've run across a lot of women online who drink red raspberry leaf tea in the third trimester, because it's supposed to help prep your uterus for birth...