5G Heterogeneous Networks (HetNet) deployment of low-power with low-cost Small Base Station (SBSs) such as Picocell and Femtocell BS (PBS and FBS) establish a precious solution for improving the musty Macrocell BS (MBS) capacity, reliability, and coverage, etc. This paper studies the SBS distribution effect on the overall performance of the cellular network. The homogeneous Poisson Point Process (HPPP), Poisson Cluster Processes (PCP), and Matern Cluster Processes (MCP) are considered as distribution models used for this study. The cell association algorithm that is being used in this research is Cell Based Association algorithm (CBA), which is based on Nash Bargaining Solution (NBS). The challenges addressed in this paper feature the HetNets cell association work in three tiers with the perspective of newly emerging WiGig technology. Another challenge addressed in this paper is the user distribution method consideration. This paper assumes the user is distributed based on non-uniform user distribution model in which the user density depends on the distance to the associated BSs. The MCP distribution model achieve optimality (14% & 8% increase in total System Data Rate (SDR) and total Jain's fairness index (JFI) respectively comparison to the HPPP and PCP). The MCP distribution model has the advantage of taking the dependence between MBS and SBS into consideration. Another advantage of MCP is that the data rate depends on the density of spatial area and is very closely affected by it, as is the case in PCP, while this property is not considered by the PPP distribution model.