second hand smoke outside??? /:

I was around a group of people today and didn't have anywhere to walk away from the situation, so I just stayed a good distance away while the breeze was blowing in my direction making the air as fresh as could be, but they were smoking weed and I don't know if I should be worried or not. I've googled everything and couldn't find any kind of help or Input really. 
I didn't really smell it but there was times I did if someone would walk towards my direction I'd get a wif of it. 
I've never been in this kind of position before and I don't know if I should worry or not because I've never even been around cigarette smoke like this. I've done everything to always stay away for things like this. 😔 
I'm 30w and really been upset all day with the person I knew at the situation and how incredibly selfish and uncaring it was to put me in that kind of environment.