What are some hints to tell if a guy is falling in love?

Been dating a guy a little over a month now and I have to admit I really like him but from what I can tell he seems to feel the same he just gets very shy around me. We spent the last few hours of our night laying in his bed just talking (we didn't have sex or anything) he said lots of kind things like "i never thought I'd be happy again" but there was one thing he started to say but said "nevermind I'll tell you next time".. I'm just wondering are there any hints a guy is falling in love with someone?