For me it varied a bit based on what stage I was in.
Pre transition I was complacent, hopeful, eager, and worried
Starting transition I was very dysphoric about body parts like hands / shoulders / hips / feet / facial hair. I was very excited too though and tried to look past it- as hard as that was.
In the last couple of months a lot has turned around for me mentally, though. Being farther along seems to have made a huge difference for me. I've been much more relaxed. Feelings of dysphoria are still occasionally present, but I feel like I've become much more accustomed to dealing with them quickly and effectively. So basically, the thought is fleeting now and doesn't bug me for more than a split second.
You just have to think of the good things. Remember that you are indirectly surrounded by people just like you dealing with exactly the same thing. We are all in this life thing together

So, bottom line I think it can make a difference how far along you are. If you are still just starting out, know that it does get way better. If you can stay focused on that (having a little thing called hope), you will not only feel more comfortable with yourself- but also greatly ups your passability if you are full timing it.
Hang in there, the feelings will eventually even out and the rollercoaster of emotions will eventually subside. Part of the journey is learning about yourself which can make this process so amazing. After a while, you will be an expert on dealing with your own emotions- and that is definitely something worth looking forward to and working towards.