Try not to worry too much about it, if you can. What you are feeling is quite normal for a lot of women.
My pregnancy was a shock too and it took me a very long time know actually be at one with the fact that there was going to be a baby at the end of it. I felt stressed for a lot of the pregnancy, and with hindsight it was because I just wasn't prepared for the pregnancy. I'd always imagined deciding to have a baby, trying to have a baby, being healthy, being ready - not sideswiped with an unexpected pregnancy. And not having had all the "last hurrah"s I had promised myself, like a girl's holiday, losing a bit of weight, quitting smoking how I wanted to quit not cold turkey with no warning, which did not go well at all. I don't think that helps how you feel at all.
I also didn't like it when the baby moved for the first few weeks. I really disliked the soft, gentle movements around 20w or so pregnant, and preferred it when the baby was much bigger and the movements were a lot more obvious.
I found finding out the sex helped me a lot because I started to think about my daughter, not "the baby". But don't worry if that doesn't happen for you. Every women will have a different moment where it all clicks into place and they feel excited and like a mum to be. For some women that will be when they get that first positive test result, for other women it might not be until the baby is actually born.
Try not to stress about it too much, as that's a vicious cycle anyway. Remember that your hormones are going to crazy at the moment too which really doesn't help, it can make every emotion very extreme.
And I know plenty of women who worship the ground their children walk on, who can cope with all the crying and the worry and the mess and the endless playing of the same game for three hours for their child, but can't stand other children. That's perfectly normal too 