How Do I Get Rid Of This Hickey?

Won't go into the sorted details but basically I told the guy NOT to leave a mark, it felt like he barely kissed my neck, but a few minutes later I had this damn hickey and its really obvious, I didn't think he sucked so hard. I covered it with make-up but it's so hot out here that it wears off quickly from the sweating. I've been hiding from my family the whole day. How long will I have to keep concealing it? Will it fade in 3 days or 3 weeks? I know now I shouldn't have trusted the jerk not to leave a mark (I think he did it on purpose). Help somebody, I don't know what my parents will say if they see it. They are uber strict. And no, I'm not a kid, I'm over 18.