Please help..........? :(?

I really fell hard for a guy. Uh..let's just call him Mitch. I was really really happy when I was with him and when I talked to him. We had such a connection. We got along so well. Basically, it's like this. Before I met him I was very insecure with myself. And he pretty much convinced me that I was beautiful and amazing. But now he says he's not sure if he feels the same way for me anymore. And now I feel like a worthless pile of junk. Everyday feels dead for me..I'm hurt and I can't smile anymore. What should I do?