How do I know he feels chemistry too?

You can figure out if he feels it too by observing his actions. Body language says a lot. If he's talking to someone else but his torso and/or his feet are still pointing in your direction, that's a good sign. Lots of eye contact is good, along with a quick half-second eyebrow-raise when he sees you. If he touches his hair or something like he's fixing it when he sees you, that's yet another good sign.

Same thing goes for figuring out if he does this with every girl. Just observe him and how he acts with other girls, and soon you'll have your answer.

Oh, and also, if he sticks around you he probably likes you. Guys don't hang around girls they don't like.