My macbook pro made a weird sound?

I was just watching a video, not touching any keys at all when all of a sudden this sound came up in my headphones. It wasn't a glitchy sound nor was is and audio problem sound. It was like sound that would have the property of any other mac sounds in the preferences but when i checked my sounds it was none existent, none of them sounded that way.

The sound is hard to describe. It wasn't continues, it was short and it happened about 3-4 times. Twice closely in intervals and the third time was a little while after.

When i first hear it, i was confused about it then I covered my webcab thinking it could be some sort of hack that access cameras..yeah idk about that it was just a reflex thing i guess.But he weird part is that the sounds immediately stopped when i covered the webcam then when I uncovered it one last sound was made just like a second after i removed my hand, the noise came back for one last time. Weird coincidence maybe?

I would like to know if something like this has happened to any of you. And I clarify, the sound was audible like any sound played on a mac, I heard it through the headphones and without them. The audio did not come form the video, I checked and also I checked if there were any pop-ups and or any other opened web page that could have maid the sound but there were none.