Everybody stutters sometimes. Your friend probably just felt a little bad for you if you were struggling. If it really bothers you you could mention it to them and see what they say. But you aren’t any lesser for stuttering even though it feels so embarrassing and stuff when you do it in front of your peers. One time I stuttered in front of my college class and had a hard block and my eyes kinda went back in my head. One of the teachers in the front row literally made a crazy face like “wtf!!!” and turned to the students to show his reaction. It sucks but try to not take it hard; try to laugh at it.