Should I dump my boyfriend?

I have been going out with my boyfriend for only 3 days now but i'm stating to have doubts. One of my friends has told me i shouldn't go out with him because he thinks he's 'hard' and bigs himself up which i find to be untrue. Another time, someone of Facebook who goes to my school told me he is a '****' and i could do better than him. He isn't the most good looking but i really don't care about looks one bit, he is so very sweet to me and i like him quite a bit. What should I do, please help?