It's simple. When you play with fire, you get burned.

Where were the parents in all this?

My kids had plenty of sleepovers and games they made up, like midnight football. NEVER were any of them allowed to have co-ed sleepovers or left to their own devises. They weren't always aware of my presence but my eyes and ears were always focused on them, making sure that things... or their imaginations didn't take them to places they were too young to handle. Sounds like this is what happened with you.

At your age, you have the hormones raging but aren't equiped emotionally to deal with the consequences. Time to stop all the co-ed sleepovers or being alone where things could go beyond what you are ready for.

Take care of YOU. Keep YOU safe.