I regret the times I've been mean to people... It's fine to pick on people who can defend themselves and deserve it. Some people don't deserve to be picked on who I picked on, so I don't do it anymore.
The REM and Nirvana successes don't mean much to me except as a potential distraction for bands who want to cash in on the trend. Don't try to sound like someone else. REM and Nirvana don't sound like anyone else.
No one told me about boys. I had to figure it out myself. The first thing I learned was that sometimes they grow slower than women mentally.