need opinions??

i’m a 15 year old female and i’m turning 16 in may. My boyfriend is 18 and he turned 18 last November. We’re about 2.5 years apart. Is this weird?? I sometimes feel ashamed because he seems so much older when people ask about his age. We go to the same high school. he’s a senior and i’m a sophomore. Can anybody tell me if this seems inappropriate to you or if it seems totally normal? also we’ve been dating for 11 months. we started at ages 14 and 17