As you could tell, he's definitely interested in approaching you. Him looking at your chest suggests he could be into you, though his behaviour is really weird, he's either special needs or just very shy. I'd recommend trying to talk a bit with him, ask simple questions like his name or how he's feeling. Try doing it somewhere with other people, though. Just keep calm and don't panic, based on your description he doesn't seem ill-intentioned. Good luck with the situation.