According to this news story a man was told at a polling station that he should not be voting.
What can I say, other than if true I find this really shocking. The idea of disenfranchising people is not what democracy is about.
The story says that the returning officer has launched an investigation, so until the investigation has finished there will be no proof that the alleged event happened, not will the person be able to be identified. Needless to say that if it happened then it stinks.
Making an ass of myself 
Those I work with, who are over 18, and understood what they were doing (after much discussion and encouragement to believe that had every right to do so) most certainly did vote.
Good for them (and you).