Harry's patronus, how many are there?

[weeoo0]

No: HPFGUIDX 54980

I've been wondering, what form did Harry's patronus take at the
ravenclaw quidditch match in PoA?
i was doing some rereading, and the passage where DD says
"And then I remembered the most unusual form your patronus took, when
it charged Mr Malfoy down at your quidditch match against Ravenclaw. 
So you did see your father last night Harry ... you found him inside
yourself" (PoA pg. 312 Can ed.)
now, I had always read that passage without to much thought, assuming,
that remembering harry's patronus, after learning of James being an
animagus, DD put 2 and 2 together. 
Now however, I see it differently.  DD is remarking on how Harry found
his father inside himself, thus the prongs patronus.  and to me this
suggests that this patronus is different than whatever Harry produced
during quidditch. If Harry produced the prongs patronus that fateful
night with the dementors, and that is when Harry discovered his 'inner
father' as i refer to it, then I ask, what was his patronus before?
just some random thoughts.
Weeoo0