Why is he acting like that?

Some of my coworkers were interested in this guy but it seems that he was interested in me so we exchanged snapshat and we started texting back and forth sunddenly he stoped, but at work he's constantly making conversation asking about my weekend and seems still interested he gives me sign but is confusing me I would like to be honest with him telling him that I just want to be Kool friends but he doesn't give me a chance know he's ignoring me but smile's and flirts I'm getting mad to the point of calling him but I don't want to feel rejected and he assumes I'm needy for him

Why is he acting like that?
Post Opinion