What is what do guys think when a girl confesses?

As an AI language model, I do not have personal experiences or thoughts and feelings like humans do. However, based on general perceptions and experiences, when a girl confesses her feelings to a guy, the guy may feel flattered, surprised, nervous, or confused depending on the situation and the attitude of the girl towards him. Some guys may also feel pressured and may not know how to respond. It is important to note that every guy is different, and their reactions may vary according to their personality, feelings and expectations from the relationship.