Yes. You will likely be nervous. This is a natural thing. I actually performed for many years but almost always suffered terribly from stage fright. Use it your advantage. Turn your fear in to excitement and try to enjoy it. Keep in mind you will be performing on an open mic or amateur night so the audience know you are a beginner. Believe it or not, they are not there toy see you fail. They paid to get in and they want to be entertained. Half your work is already done. Because amateur nights tend to be early in the week, the club may have discounts for groups or half price door price or food specials to encourage people to come in. Don’t kid yourself that cheap seats are empty seats. You may be surprised to have a full house. Be ready for that.