I had the same problem though my situation was slightly different. I'm on day 5 of no porn and the rationalizations have set in. As an extension of a rationalization, I had gotten triggered (to which I navigated away from that potential situation) but that trigger led me to want to google a question about sex for learning purposes. Well low and behold, porn was present. I too immediately retained my wits and shut it down. I think you need to come to the understanding that because porn is on the internet, there is a very high likelihood that you'll stumble across it from time to time. Whether you had no intention to even see something like that or are like me and have a legitimate question you want answered about the subject of sex or something related and you see it, it is bound to pop up. But like the fine gentlemen on this thread pointed out, the point isn't to shield your eyes from all porn forever lest you reset and fail. The point is to change how your mind reacts to these images and how you exercise the will to stay the course of being free of this vice. So don't beat yourself up, don't get mad, don't react. Accept that this is just a facet of the internet and just navigate away when something you don't want to see pops up on google. It is as meaningless to you as a random person's opinion on Facebook.