My boyfriends parents don't think I should be in love right now, let me explain and tell me what you think?

I have been dating my boyfriend for 8 months now, 9 on June 4th. I have known him for about 4 years now. I Love him deeply and he loves me back. He makes me laugh and makes me smile when I am down. He does not pressure me to do anything I do not want. He cares so much about me. He says he would die all for me, and he would do anything for me. He is sweet, kind, helpful towards others, and honest. He shows me he deeply loves me in so many ways. I love him so much. He makes me happy. He makes my day shine brighter than it has ever shone before. When I hug him, I feel a warmth and I feel protected and safe from everything. He is always on my mind, everything I do reminds me of him somehow. My heart skips a beat everytime I see him. He is very patient with me on everything. He holds me tight when I cry and is always there for me when I need him. I show him I love him by creating things for him, for his birthday and just randomness to show I care. When he leaves, I want to cry and bring him back to me. When he leaves, I miss him so much even though he has just left. Now, I love his parents, they are super sweet and kind individuals, but they think I should not be in love at my age. That I should get a little older, to truly know what love is and be able to say I love someone. I do not disrespect what they say at all, I respect it. I was just wondering what you guys think of the situation? Should I be in love at the age I am now? I am 18, so is he. He will be 19 in a few months.