How to tell if a guy likes you or not?

So, there is this guy who at first I wasn't very interested in, but after talking to him more I kind of am, but I don't know if the feelings are mutual. I'm in college and we've kissed a few times, but it's been when we've both been drinking a little bit, but in that case it is always him who texts me, although I don't know whether or not to equate that with the fact that he may just want to be with someone for the night, but he has suggested that we get lunch sometime, but due to it being the end of the year and being busy with finals it hasn't worked for either of our schedules, and we talk almost every day and tend to for the most part have pretty long conversations about the most random things, but it tends to always flow, I don't know if that's because we both tend to get bored or what though. He slept over the other night, we didn't do anything though, but ended up talking about his exes in college, he brought it up not me, and he asked if I had had any college relationships, which I haven't, but I thought it was kind of a random conversation. We'll both be home for a month due to winter break, so we won't see each other for a while, but I was just wondering what he's possibly thinking.