A very close friend of mine recently came out as a male transgender...

A very close friend of mine recently came out as a male transgender, and I don't know why its bothering me so much. I've known him closely for about 2 years, and I always sort of thought that he was trans, but I never forced the topic. He recently started his coming out process, I was in the first group of people he told.

Since then, 3 days ago, i've had a lot of trouble eating, and I have a constant feeling of nervousness for some reason. I really want to be there for him, but I'm worried that i might not be able to be 100% supportive in every decision he makes, and I think that he really deserves as much support as he can get. I'm really stressed out. I don't want to be the person that lets him down, for any reason.

Some background on me so you know i'm not some homophobe (I know being trans isn't the same as being gay. For me, homophobe is just a general hate against any LGBT area). I'm gay but not out. The first person I told was actually my friend shortly after him coming out as trans. I thought it would be good, if we had a sense of togetherness between us for the both of us.

I really don't want to offend him, or hurt our friendship in any way.

So anyways, my questions is "is it normal to be so worried about the whole subject"?
If you have any other commentary, it'll probably be welcome.
I'd love to hear another "friend's perspective".
Please don't bring religion into the question. We're both athiest/agnostic.