Selective Laser Sintering (SLS) of poly(ether ether ketone) (PEEK), a high-performance polymer, presents significant challenges due to its narrow processing window, high melting temperature, and low thermal conductivity in powder form. The successful fabrication of highly functional, dense components necessitates precise control over the intricate thermal and fluid dynamics governing the PEEK sintering process. However, experimental and single-physics modeling approaches are often insufficient to capture these transient multi-physics phenomena. This study introduces a novel two-dimensional (2D) multi-physics Finite Element Analysis (FEA) model to simulate the SLS processing of PEEK powder. This study realistically models the transient thermal and fluid behaviour during the SLS process and evaluates the effect of fundamental parameters such as laser power and scanning speed by incorporating combined multi-physical phenomena such as heat transfer, fluid dynamics, and phase transformations. Although optimum thermal profiles are obtained at an Energy Density (ED) of 0.03 J/mm², it has been determined that ED is not the single factor in understanding the thermal behavior. The results show that scan speed significantly regulates heat accumulation and thermal gradients. Slower scanning speeds promote high heat buildup and surface degradation at low powers, while higher speeds limit thermal penetration, increasing the temperature difference between the top and bottom surfaces. This computationally efficient 2D multi-physics approach improves understanding of PEEK laser sintering mechanisms, providing quantitative information for rapid and effective parameter identification in high-performance polymer additive manufacturing.