something to worry about?

in going to a certain site i pasted the address into the browser bar. clicked enter and then saw the blocked box pop up for a split second, then it quickly vanished and the site loaded normally. should i be worried since i saw it pop up but it is showing no detections? i will also do scans with other av's to be sure but why did this happen this way if the pop up came up and the site was blocked should it not have gone away within a split second (i saw the pop up and it went away so quickly i could not read it or see what it said)

 

You should be fine - it could have been a script which tried to load in the background but timed out/no longer existed.

 

thank you for the info