I've been with my boyfriend for almost two years. We're past the lovey dovey stage but there's so many great things that come with that. You're now at that stage where you're completely comfortable with him and you know that he'll love you no matter what. A few months ago, I got ill with a stomach virus while I was at his place. If he was still able to say "I love you" and want to be around me even when my head was in the toilet and my skin was close to a shade of gray, then I know that we're meant for each other.
In all seriousness though, most couples get to that stage where telling each other all the time that they love each other is not the way to go and sometimes they will fight over stupid stuff. I look at my own parents who have been together for over 25 years. They aren't all over each other (THANK GOD!!!) and they get annoyed with each other but, at the same time, they truly love each other. Do you truly love your boyfriend? Then that's all that matters.
And, yes, I will tell my boyfriend flat out that he's annoying me but I am a very blunt person so that's just my personality.
That's what happens when you spend a lot of time with someone...you're bound to get annoyed. Take up a hobby or have a Girl's Night Out once a week. That'll keep the two of you out of each other's way so that you won't get as annoyed.