Is a guy interested in me?

So I went abroad with a group of 18 this past May. A certain guy on the trip I had talked to and kinda knew beforehand. On the trip I noticed he always sat by me at dinner, asked how I was, even petted me. On the 4 plane rides for some weird coincidence he sat near me and seemed to be looking at me when I looked back at him. Anyways we had a great time when we went out partying but didnt actually talk talk on the trip. What does this mean? Now we dont see each other bc its summer and we're both busy but come August I'll see him back on campus. Was he just being nice or something else? Any input would be great. Thanks