Flight Following and OOPS

I am not sure what I should do with this, so I am fishing for
opinions, thoughts etc.

I took off from an airport and immediatly requested and received VFR
flight following through some Class C which lies between my current
position and my destination. I climbed to 5500 +/- 100ft and was
vectored through the Class C. When I was near the edge of the Class C
( I estimate I was 2-3 miles from the edge of exiting the Class C) I
was asked if I can resume own navigation, and report destination
airport in sight, I reported airport in sight and the controller told
me "resume own navigation, squak VFR, Radar services terminated"

I flew along for a short time and noted I was below the 5500 ft
ceiling of the class C (by around 100ft) and immediatly climed to
5600ft for the remaining couple miles.

So... Obviously I was in the Class C, and though I was still on
approach frequency, I do not think that I was still in radio contact,
right?

Is a NASA ARS form appropriate? Was I wrong and did I bust the C?
Mike Flyin' 8