Just asking about my drug test coming later this week

Hello we'll I am kinda freaking out. Let me tell you the story well last month I was at a party and I had one hit from the bong I haven't smoked week since tenth grade this was my first time in ages what I'm wondering is an I clean or do I have to worry? My height is 165cm and I am 51kg(skinny I know.) I hope I am just over exadurating

If you only hit once and haven't smoked since, no worries.