Does this guy like me, or is he just trying to be my friend so he can ask if i like his best friend?

so, there's this guy (lets just say his name is bob) and i sit next to him in science, and me and him are the only ones at this table. so from the beginning of september to the end of november, we never spoke to each other. we never said "hi" or "how are you?" or anything like that, we just pretty much ignored each other. and whenever we had to talk to each other, usually about sciency stuff, he acted liked he was pissed at me. but than in the beginning of december, he forgot his science project, and for the whole cl we had a pretty friendly conversation about it, and how he thought the teacher was going to kill him. and every day after that we would talk throughout science, about all different stuff. and than the day before winter break, we had this embly, and we sat next to each other (i sat down n that he just followed me, but i didn't mind) and we talked the whole time again. then the guy sitting next to bob turned to me and said "i love you" (he's a really good friend of mind and he says it all the time, and he was also meaning like a brotherly sisterly love), and i said "i love you" back. so than bob said "i love you both" and than he sorta hesitated and stuttered when he said "i love you guys mutually", almost like he didn't want it to seem like he loved one of us more. and of course i said "i love you" back, but i was sorta in shock that we've only talked to each other once a day (each day, so 5 times a week) for 45 minutes for like 2 weeks, n he was saying "i love you" to me. i was really curious about why all of a sudden we went from not talking to each other, to like being really good friends. i was also wondering if it was just that bob was trying to see if i liked his best friend, cuz his best friend might have thought i was flirting with him a lot. but i don't like bob's best friend more than a friend. and also for a while, like in september, i did think bob was cute, but i only told 3 of my best friends, and i know that they didn't tell. and if they had told, word probably would have gotten around that i liked bob, and people would've come up and asked me if it was true. like, i really wanna know why all that happened. what do u think was the reason, and what should i do? oh yah, i'm a pretty shy person, so i probably wouldn't have the courage to confront him and ask him if he likes me...