Boyfriends best friend

hi ok so this is weird but idk if im seeking advice or just seeking to see if i may be wrong in this situation. My boyfriend has a best friend and the guys is really nice! Hes someone you can trust but in the past few months i can tell hes just been overly sensitive towards my boyfriend.. almost having the same issues a girl might have towards her boyfriend. He gets sensitive in random situations revolving my bf and since its summer ive been catching on to a lot of his pettiness and just overly emotional thinking. He is 21 and my bf is 20. My bf had to stay on campus for the summer and well his best friend decided to stay too. I know that my boyfriend didnt like ask him to stay or you know what i mean, but his best friend decided to stay himself. When i would speak to him he’d make comments like “yeah i wanna stay here as long as i possibly can” when i would ask him how long he was staying. (Mind you hes not allowed to stay on campus). My boyfriend is a sweetheart and i know he loves him but he does notice this obsessive personality traits coming from his best friend. Its like his best friend cant live without my boyfriend, cancels out other people in his life because my boyfriend is the only good friend. Now since hes staying for the summer, when i come over to see my boyfriend, its always the three of us together. Unless his best friend leaves to the store or what not we basically do everything together. Again, his best friend is a good guy and i definitely don’t want to seem like i want my boyfriend all to myself but there are just some things his best friend does that i find a little bit abnormal in a way. I find myself feeling weird around him too and i mean idk. I just wanna know if i may be in the wring? I did mention it to my boyfriend but i dont want to appear like im talking shit about his best friend... im not i just literally find it a bit concerning. Like today my boyfriend was hungover and we watched a movie together with.. his beat friend and i was getting ready to go and his best friend got up so i could get my stuff normally. He was leaning over the bed at my boyfriends feet and bit his foot! And idk again maybe im overthinking but just shit like that makes me feel a little concerned and i just want to see what other people think lol. Its just hea supposed to be going home and his mom is like waiting for him and is upset with him, but he chose to stay because my boyfriend is staying.....