Relapse or not

Hey guys,

I have been on this streak for 90+ days Monk Mode. But something happened today while I was watching a tv series online. I was 5 min into the second episode of Billions when suddenly a sex scene came. I was startled but also it did pique my interest. In less than 5 seconds I buffered to some other point in the video. However the next thing that happened shocked me. After about 5 min, I again went to that scene. This time though I closed the browser itself in 5 seconds.
Now what the scene included:
1. Moaning sound
2. Face of a girl exhibiting those expressions of being in orgasms
That's it.
It may have shown something else but I didn't see it after that.
My 1st question: Is this a relapse? Should I reset my counter?

Also I am seriously shocked as to how quickly I forgot about my NoFap journey and everything I that i had gone through to reach this point. The sexual desire is the strongest desire of a human and today I experienced that.
My 2nd question: What to do about these sudden external stimulation?