Being sexually active and STDS

So, I see a lot of posts about body counts and etc and some girls go up to 30 or even more, and I don't find anything wrong with that but I have questions. So, when being so sexually active have you ever came across an STD or even a silent STD? And if you had clme across a silent STD after being diagnosed did you then realize you were getting symptoms of the STD but because it wasnt so noticeable you never realized? And what is your body count and have you ever had an STD? STDS are honestly just a huge concern of mine because so many people in my high school sleep around with so many people and I doubt they ever get STD checks so here I am asking older and more experienced people about what happened to you guys!! (I'm not sexually active, just comcerned for my friends)