Lol, I can see why he only talked about the colour. This is a very sweet quote, but maybe he's not ready to say that he's in love with you yet.
It is a sweet gesture to send it to him. But he clearly isn't ready yet to talk like that.
I don't know if I would read into this too much. It really depends how long you two have been dating. If it's only been a few months to a year, then let it go. If it's been a few years then maybe you have something to be worried about.
If you haven't been dating that long, maybe it's just coming off as clingy and he doesn't know how to respond. Doesn't mean he doesn't like or care about you. Sometimes, guys such as myself have noticed that being "distant" actually increases a girls interest in you sometimes, so maybe he knows how things work, lol.
Personally, I like clingyness and I get attached quickly myself. Technically most guys fall in love quicker, but we're usually less quick to be open about it.