Obsession

I need some help on what to do next , so at my work place I have a crush on this guy for a while now and I really want to get to know him more but don't want to seem desperate and I dont show emotions , so I did the hints and he seem also to like me he even admitted that he has been thinking about me alot and attracted to me but scared to make a move because we work together and that might be tricky and might effect our relationship between us and he's scared I will get hurt he said if I have something else to say or I have another prospective to share it with him.. I said I will but I didn't I was scared I waited .. and he didn't mention it again we were flirting at work and joking like usual then texted him that I wanted to talk to him when he Finnish his shift he texted back that he Finnished and I didnt talk to him I got busy so I texted him the next day sorry I got busy he didn't replay and at work acted like nothing happened and either of us mentioned it again... but lately its been heavy on me I cant focus at work I cant be myself around him I just feel stuck like I want to get to know him more and on the other hand I cant decide if he even wants that , lately he's been cold towards me and distances him self at work from me , we work very close together and is starting to effect me alot I miss our jokes I miss him and I'm just acting like I dont care and just role with the punches but its really annoying he flirts a bit then keep the distance so should I confornt him about how I'm feeling or just to let it go ? or just to ask him why he's acting different around me ? It's really affecting me alot I'm becoming obsessive and can't sleep I never liked someone that much and its killing me to act like I dontt please help what should I do