Clarity in thoughts

It takes me a long time to express what I feel in words. It was a nagging pain from the beginning but nowadays it has become a full-fledged worry. i seem to be carrying the same into my professional life as well. Why is this happening? I am never able to tell anybody what I feel clearly. It is like I'm thinking one thing but just gibberish comes out of my mind. The last time I had a bad mood, it took me ten days to tell my near and dear what was bothering me, and not before giving them a hard time about it. Even in my work, I notice that I am too short, too concise and basically not very clear in explaining things. My mother has a weird theory of my being too impatient to get on with a train of thought too long to express it. Maybe, she is right. I don't have any clear answers as usual. But I would like to overcome this obstacle before it becomes a handicap. I hope I have expressed myself clearly in this space....