Don't worry too much about it, once you begin your studies you'll see that all of your fellow students want to make new friends at the beginning. Ersti-Week is build around making new connections and even for me as a very shy person it was really easy to talk to people. Take advantage of the activities that are offered and just be open. I study medicine in Bochum and have lots of friends who came to Germany only months before beginning their studies (for example, I know a lot of people from Syria). Language has never been an issue and you aren't going to be the only one coming from the Middle East. Let me know if you have any questions about the RUB!