Problem

I just found out that I got some difficulties. I got some serious problem bout expressing my feeling or maybe thoughts. I can't tell people what I really feel or what I really want to say. I don't know why but I found that its hard for me to be honest with others. It doesn't mean that I lie, it's like I like to  keep things or some unhappy feeling in my heart without telling others. And seriously,  it's killing me.