I'm gay but I've denied it every time people asked before so am embarrassed to come out. What should I do?

For my whole life, I have avoided the possibility that I could be gay- as a young child I only considered a future with a woman. Although most of the people I have met have questioned my sexuality (e.g. family and friends), I have always strongly denied the possibility. I have a feeling that they do not believe me (maybe I'm just overly suspicious). But, now I have realised that I am gay and do not want people saying 'I told you so' or asking why I denied it before. Should I come out anyway or should I wait till University (only a couple of years) when I can start afresh?