Personally, I've always been a very independent person. Until college sure, I had dated, but I never had a boyfriend. When I finally starting entering into relationships, I realized that there was so much about them that was new to me. Here are my thoughts.
1) It's hard to get used to the idea of being in a relationship
To this day, I still get excited inside when I hear the word boyfriend in reference to the guy I'm dating. It's not that I ever forget I'm in a relationship, I'm just simply not used to being attached to someone else. You may be used to being totally independent, and it may feel surreal for a while when you are finally committed to someone. It can be a great feeling though.
2) You're used to be self-focused
Maybe you're used to having your own schedule and agenda. It can be hard to remember that when changes in your schedule occur, you should probably notify your significant other. You're also used to focusing on solely taking care of yourself, your own needs, wants, and goals. It may be a difficult learning process to bring someone else's needs, wants, and goals into the picture as well.
3) You're no longer accountable only to yourself
What you do and the choices you make no longer only affect you. They affect your boyfriend or girlfriend too. If you are having a bad day, you may cause them to feel a little down too.
4) You're learning as you go
Because there's so much you don't know. It's all so fresh and new and may take quite a bit of time for you to get used to no longer living the single life. There's so much to learn and the only way to figure it out is to do it. This can be tough, especially if the person you're dating is a lot more experience than you are and knows all the ropes. It may take a lot of patience on your significant other's part, which is not always easy to find in someone.