am I to young?

The guy I'm dating is great, and I really care about him. He's very mature and has everything planned out and I really enjoy being with him, his maturity is the same but his age is not he's a couple years older than me 3 and it won't be a big deal in the future I know but at the age I am I'm getting a lot of hate about it. I'm 14 he's 17 and we both want a long term relationship. I kind of just want opinions on this idk what to say to other people or think because I'm young, but I am very mature for my age, I have a plan and am ahead in school. Mentally I'm so much older but I'm still young and at our age I don't know what to think