Direct current N2 flowing discharges were generated and conditions for the pink afterglow were obtained. Emissions from N2(B, C) and N2+(B) radiative states were studied as a function of pressure, flow rate and post-discharge position. A one-dimensional kinetic model accounting for N2(X, v), N2( A, B, C, a, a', a''), N(4S), N1-4+(X) and N2+(B) species has been developed in order to describe the experimental observations. The analysis on the complete set of processes assumed in this paper has provided possible generation mechanisms for N atoms, N2+(B) ions and N2(B, C) electronically excited states as well as for metastable ones. It has been shown that ionization, excitation and dissociation processes occur simultaneously at the post-discharge region when the vibrational distribution function of N2(X, v) states heats as resulting from the efficient V-V pumping mechanism, which is very sensitive to pressure conditions. Here, the pink afterglow is described as a non-equilibrium plasma, i.e. ambipolar diffusion for ions and the condition of charge neutrality are assumed.