Haha, well at least it's a bit of a compliment for them to wonder why you are single! One look at me and the disgusting beard, bed hair, yellow teeth and perpetually stained undershirt must make them keep those questions to themselves!
But I wouldn't interpret that as you being put under pressure (just because somebody asks). Maybe you feel the pressure from within because you know your time is running out to get a girl before you're 40 and by then will not be able to enjoy a woman in her youth