Caviar while 5 weeks 4 days pregnant??

Accidentally ate the amount of caviar that would fit on a nickel...I’ve read probably 40 different google websites and I’m mortified of getting listeriosis (listeria) and I’m so worried I can’t sleep. I don’t think the caviar was pasteurized as it came from a restaurant. Is there a huge worry? Anything I should do? My first doctors appointment isn’t for about 3 weeks.