Search Results: body language that he is interested

So I don't see the guy I like in person all that much but when we text he is almost always flirty with me, interested in what I'm saying, and uses the ":)" emoji, which is hard for him because he doesn't have a smart phone and still has buttons. He does sometimes text first (actually he texted me first as I was typing this and he is replying really fast). He has complemented me on my outfits with the smiley. Yesterday I went with him and his family to the movies and it seemed like he intentionally made it so I would have to sit next to him (the family takes up nearly the whole row and there was only one seat on a side because the one next to it was broken so I had to go all the way around and sit on his left). we talked and made comments throughout the movie he was very fidgety (kept running his fingers through his hair, bouncing his leg, tapping his fingers). Though he does basically refuse to hug me even though all of his siblings did. I've also been told he gets super jealous when he is reminded I was friends with his older brother first and got really upset when he thought I texted his sister first to let them know that their college was closed (when in reality I only texted her because he wasn't responding to the one I sent him). The last time I was over for dinner his face and neck turned really red and he kept stareing at his shaking hands, which he blamed on too much caffeine, but as soon as he left the room he was fine so was I making him nervous?
This all sounds so positive but at the same time it is really confussing. I heard from his sister the other day about a girl he liked at school and how they drew on her dirty truck to say goodbye to his feelings for her because she got a boyfriend. If he really liked her I can't help but wonder how he really views me. He has called me his friend but he sure doesn't act like one and I can't help but wonder if he is viewing me as a possible rebound or as just a toy in general. I could really use some help

I was walking into this event that I was meeting my boyfriend at. A bunch of his coworkers were there too, and he just happened to be talking to this woman he works with. I froze and watched for a few minutes and it's obvious that she's interested in him. She kept leaning close and laughing and playing with her hair. Eventually his body language changed too and he was laughing and playing with his hair back and he looked nervous (like he did when him and I first started talking). When I came up they both got serious suddenly.
It's just that she's soo beautiful and I've been jealous of her since we first met and I know she's more attractive than me.

Should I be worried?