Regular expression - count newline characters

[Ashish Shinde]

I have a requirement to count the number of newline characters in a varchar2 field in Oracle.
The catch is if the line starts with characters 'SS' it should be ignored in the count.

E.g.: -

This is
a test for
SS not included
so ignore

should return the count as 3

Is there a way to do this using regular expression ?