The problem was that the previous wisher had seen a popular movie
called
Guams the Mighty which featured a 3 headed dragon that could take to the air
on leathery wings with a dwarf and his pony clutched in each of Guams legs.
So 4 wailing ponies and their riders meant one big
dragon.
This wisher has tossed in a copy of the movie into the well
but hadn't had the required 25 cents.
So Bob rushed back to his car to get the required quarter,and in
the meantime you had blundered in and tossed in your 25 cents\and wished you could fly long distances carrying a lot of weight.
You'd been thinking practical
start your own airfreight business
Alas the Well had been watching Guams the Mighty in the meantime
and had noted this 3 headed Death in the Night
beasty could fly long distances
as well as haul 4 dwarves and their ponies
Clearly you'd wanted to be turned into
Guams.
So you kept changing and getting bigger
and barely made it out of the Castle before
the really serious transformation kicked in.
So out you staggered,positively full of
<DRAGON> and the third head <You> in personality,kept getting
outvoted by the other two,clearly <Guam the Mighty>