LSD... I tried it two days ago, will I ever be the same?

Basically, LSD isn't going to make you go insane. The people you see that can't form sentences and can barely see straight have been using not only LSD but probably many many different drugs for decades. If you use LSD on occasion, you WILL NOT go down that road, trust me. As long as you keep it to like five or six times a year, you'll be mentally fine and spiritually transcended.