Yes, guys occasionally heart messages. They do so when they like what you said, when they like you or are grateful to you.
That he texted you a heart. He can interpret it to mean whatever he wants. It could imply that he likes you or that he's just acting like he does. Words don't mean much since they can be twisted or used against you; you should base your decisions on your actions instead. And if a text message is unclear to you, you should ask the person who sent it to you.
