After being sexually active for over five years (now being twenty years old) I finally got myself tested for chlamydia. I received the results today and found out I am positive for it. I have slept with over twenty people in this time, do I have to tell them all?

I have no idea who I contracted it from, if I have had it for a while then could it mean I'm now infertile?

Also I'm going to collect my prescription tomorrow, when do I next need to get tested? Any help would be wonderful! 💕