Should I mention the awards I won to a potential masters supervisor?
Yes, you can (and should) mention that you already have research experience (did you also do the writing yourself?). This is an appealing skill when choosing between master students who want to do their thesis project with a senior researcher. However, I would formulate it more humbly. For example, "I already have some first experience with academic writing and conducting research, so I hope this will benefit the work for the upcoming thesis project. I attached my first manuscript to give you an idea of my previous work."