Definitely Graphic Designer. You now need to make a portfolio. Start by asking the owner if he will allow you to use the menu and flyer as part of your portfolio (since you didn’t charge, I doubt if he will have a problem).
Remind the owner that Yelp is very good for business and that he needs to make sure he checks Yelp and encourages people to leave reviews, especially if they like his food. If he offers to pay you to help out, then take his offer and you can then call yourself a Graphic Designer/Social Media Specialist. You might want to give him a discount if he will help introduce you to other business owners that might need your services.