Explain this please....

So I’ve been with my current boyfriend about 6 months now. Things have been better than great and I really can see a future with him. I’ve been holding out with saying the “L” word until he said it first because I’m stubborn. Well about three weeks or so ago I said it. When I told him I also told him not to say it until he meant it because I wasn’t trying to rush anything or to pressure him in to anything. Well we were out with friends the other night and someone looked at him and said “oh, you know you love her.” I just laughed it off and said “really, that’s news to me!” I let it go and don’t really think about it but now he’s doing things he’s never done with any of his previous relationships according to his family and his friends, and they’re not easy to hide things like putting my nickname on the passenger window of his truck. The more I think about it the more I don’t understand how you do things like that for someone you don’t “love.” So what do you guys think about all this because I feel like I could possibly be thinking too far into it....