accidentally coming off as cold/unapproachable

yeah til now it’s embedded into my mind what happened earlier today. I still feel guilty over it. a peer asked my friend for papers on a subject, friend said go ahead, take it; subconsciously I touched the bundle of papers which was lying in front and was going to give it to the peer who asked, when said peer immediately instead asked for another notebook of another subject that friend and I weren’t reading. I only realised, much later, that I came across as not wanting to hand them the bundle of papers by placing a hand on it immediately, and their tone from earlier seemed to express that: mixture of—nervousness and disappointment, or what it now seems to me. I can’t just go and tell them I didn’t mean to come off like that, after hours passed, when we’re not even close or talk outside of groups.

the thing is, this has been happening, I noticed, with some others as well. someone would think they offended me, would then apologise, I would say they didn’t do anything wrong, or sometimes just remain silent because I don’t know what the hell they’re apologising for. this happens when people ask me favours too.

is there something wrong that I’m doing? I make sure to smile and laugh, to use a kinder tone, but somehow I think I come off as unapproachable. how do I appear more friendly to others?