Am I losing feelings for my boyfriend *Please read, I really need help*?

[The secrets that I keep]

I will try and make this as short as possible, it may be hard though
He's 17, I'm 16. We're both of legal age in the United Kingdom for sex.
I first met him through my best male friend, when we first met he was shy so we didn't talk. This was when I was 15 and he was 16.
He spoke to me continuously online, he seemed to like me and I adored speaking to him online.
We stopped speaking for a few months as alot of crap went down but in August of this year we began chatting online again.
I agreed to meet him at the end of August.
When we met up I was shocked, he looked so different (In a bad way) I didn't mind as I put this down to him being stressed over the past year.
He was nothing special at all, I couldn't believe that I'd lusted over him for a full year, I'd even become depressed on several occasions due to him..
He asked to meet me and on the second time we met he kissed me. He'd never kissed a girl before so it was very brave of him.
He asked me to be his girlfriend and I said yes.
A few weeks later we both had sex with each other, it was both our first times.
Now I sleep over at his house once a week and I've just noticed that I don't feel anything spectacular when I'm with him, I'm never incredibly happy to be with him; sometimes I just wish I was at home in my own bed.
The thing is; I hate the thought of us breaking up, the thought makes me really upset.
I still get incredibly excited when I see that he had inboxed me on facebook or sent me a text message and I don't know why, I'm never excited when speaking to him in person.
Is there something wrong with me? I'm never nervous when I'm with him, I just sometimes wish I could be some place else.
Thanks for any answers in advance