I certainly don't think you're alone in feeling nervous. Whenever I make a large purchase, whether it's a home or a car, I always get nervous and ask myself a million questions. Am I making the right decision? Can I really afford this? What if the last one I liked was better? Am I making a mistake? Should I buy now or wait? It can really go on and on.
I also sometimes go ahead and buy whatever it is and then the next day feel buyer's remorse, which I think is common also. I always get over it, but it's that feeling of a commitment you didn't have before. Along with a home comes a lot of expenses you didn't have when renting and that can put weight on your shoulders as well, just the unknowns of the whole thing.
When it comes to buying a house, which can be one of the biggest purchases of your life, I think you should do as much homework on the city, neighborhood, and street as you can. I've heard it's really good to talk to potential neighbors and see if they like living there. I know that if someone were to knock on my door and ask what I thought about my neighborhood I would give them a candid answer. I think the more research you do, the more confident you will be in your decision.
Good luck!