Too bad you're not playing it on a REAL Gameboy where you can hit the
Select button immediate as you jump from one map section (where the screen
slides over) to the other. It teleports you to the other side of the
screen and you can find some fucked up shit throughout the game including
glitched maps and other neat stuff.
I never did find out how to keep Bow Wow the whole time, but I was able to
keep the chicken indefinitely (you'll see later).
The Ocarina is great for getting out of glitched areas when you're
stuck in walls. Don't leave home without it.