Is this normal in a relationship?

no
thats moving too fast

Maybe that's just his beliefs and that's fine. I don't think we should consider if someone or someone's is behavior is normal or abnormal just because it doesn't fit the society's view, as long as it's not hurting anyone.

I don't think you can say that his thinking is abnormal. Right now, he is love and he feels like he is on top of world. Also it is normal now for couple to have sex or even live together before they get marry. You need to see the compatibilities with each other wh ich including sex. Sometime people break up because they are not compatible in bed. So if he wants to get married after high school is his choice but usually when the boys reach that age, they change their mind about getting marry.