Re: buyer's remorse
Yes, I think there is a significant element of that. I suspected it, then my wife mentioned that a few people on farcebook made comments along the lines of "I thought my vote wouldn;t count" and "I was just voting against Cameron". Since then I've seen similar comments in TV news interviews, including on pro-Brexit Murdochs Sky News. One guys comment was "I woke up, saw the result and was in shock, now I'm worried" (this was another leave voter)
Whether it's relevant or significant I shall leave to the various campaigners and their inevitable legal challenges.
As for the petition, it does raise an interesting point. The last Scottish independence referendum had conditions attached based on turnout and minimum percentage of eligible voters who mist vote Yes for a valid result.. Note particularly that world "eligible" used in place of "actual". Since the EU referendum was for a very similar "separation", why were similar conditions not placed on it? I suspect that will be a prime point in any legal challenges.