It's probably a temporary form of derealisation/depersonalisation (dp/dr), which is harmless in itself. Your mind can 'switch' to this state in order to protect itself from problems/pain.
Keep a good eye on it though, if you notice that you feel like this all the time you might want to tell a therapist about it. I've been slowly sliding into this dp/dr state from the age of 14 and on (more or less) and I didn't really know what it was 'till about two years ago. Right now, I have my ups and downs, but on the whole, I'm still derealised.
I have to say, my discovery and knowing of transgenders didn't help with that. Especially since I now live two lives, so to speak. At school (monday to friday) I'm seen as a girl (or well, the people who know me see me as one) and the rest of the week I do my best to be seen as a guy.
So yea, it's probably dp/dr, harmless in it's temporary (and mental protective) form. But keep an eye on it, even though it has to do with your dysphoria, starting T and having surgery won't cure the dp/dr if it's already 'in you'.