First of all, secp128r1 is outdated. Use curves that give better security for today's standard. See safecurves by Daniel J. Bernstein and Tanja Lange.
An Elliptic Curve defined over a field of size q and every element -point- has two coordinates X and Y. The Elliptic Curve Secp128r1 has 2128-297-1 size ℓ, i.e. number of points a little under 2^128. This means that we need 128-bit representation.
The public key which is also a point on the curve has two coordinates, therefore, we need to store two 128-bit.
If we look at the equation of the elliptic curve Y2 = X3 + aX + b where
a = FFFFFFFD FFFFFFFF FFFFFFFF FFFFFF
b = E87579C1 1079F43D D824993C 2CEE5E
if we know X from the equation we can find Y. Since we are working in a field the Y can have at most two square roots. Y2 will have y or -y as the square root. This knowledge can be used to compress the representation of a point and it is called point compression. Just x coordinate and one bit to select y or -y. Now look at the base point (see Certicom recommendation)
base point = 03 161FF752 8B899B2D 0C28607C A52C5B86
= 04 161FF752 8B899B2D 0C28607C A52C5B86 CF5AC839 5BAFEB13 C02DA292 DDED7A83
The first octet determines the structure
04 means there is no compression
03 means there is a compression and select y as positive
02 means there is a compression and select y as negative
Now turn into OP's parameters;
04 means there is no compression. The first line is the X coordinate and the second line is the Y coordinate of your public key.
What about the private key n? It is just a scalar -integer- between 0<=n<=ℓ
Therefore, the above number - not point - is your private key.
You can also use some web tools to extract this information.
Note: please don't expose your private key.