What does it mean when a guy confides in you and tells you to be careful and to be safe?

We have worked with each other for about 6 months now and we have hung out before, and one night when I was drunk I text him and basically told him I liked him and he told me that he thinks I'm a good friend and doesn't think it could be anything else because of work. But then he basically told me the reason why he is so relationship shy and told me that he never told anyone else that we work with the secret that he shared with me. Also if he knows I'm going out he always tells me to be safe and not do anything stupid.