Think About him too much?

I think about my boyfriend 24/7. I mean CONSTANTLY. We have been together for nearly a year and I think he is perfect. All day long he's on my mind but I think it might be too much? This is my first serious lasting relationship, but I had one boyfriend before and I thought about him a lot too. 
Is this unhealthy? I mean everything reminds me of him and I'm always thinking of things he said or did. I know I'm in love with him but I'm wondering if anyone else has been through this  
Just to add we are both adults. 21 and 27 years old.