If you are being followed by someone, the best chance you have at deterring the person pursuing you is to turn around and yell firmly at them “What do you want!” whilst getting the best description of their face. This will help people that are around you know where you are whilst hopefully scaring the creep off as they will most likely realize that you have seen their face and know that they are following you.
"People having seizures cannot swallow their tongue. Do not put anything in their mouth."
It's not that people actually swallow their tongue, it's that their tongue will rest in the back of their throats restricting their ability to breathe. People have heard this and misunderstood what was actually happening and spread misinformation for decades. So then things like this come out without actually addressing the truth or the root of the phrase. Your tongue isn't going to rip out of your mouth and go down your throat. It can rest in the back of your throat and choke you to death. That's what they are saying when they say "swallow your tongue."