Is it ok?

I have one child already and only want 2. I found out I was pregnant and was so happy cause we've been trying for 3 years. I went the the dr and had an ultrasound. I'm having twins. I'm kind of upset up having two. We just moved/bought a three bedroom home and do not plan on moving ever. So now my two twins will always have to share a room. I also only wanted two children. Is it normal to feel like this? I'm not going to get an abortion... And I know this feeling will pass and in a few months I'll be excited I'm sure.... But I just feel terrible for feeling this way.