Fluorophosphate glasses with varying Cd/S ratios are synthesized. Heat treatment leads to the formation of CdS quantum dots with sizes ranging from 2.0 to 5.5. The luminescence properties of the CdS quantum dots are analyzed as a function of the Cd/S ratio, Zn2+ ions content, temperature, and excitation power. The influence of the Cd/S ratio on the quantum dot growth characteristics is demonstrated. Additionally, the dependence of the luminescence quantum yield on the quantum dot size is determined. At room temperature (RT), the glass-ceramics doped with CdS QDs (2.0-5.5 nm) exhibit only trap emission in the 500-750 nm range, with a quantum yield of 20-70 %. An increase in the quantum dots size leads to a higher quantum yield. Measurements performed at decreasing temperatures (300-10 K) and increasing excitation power densities reveal the emergence of a narrow band-edge photoluminescence (PL) peak alongside the broad trap emission band. The dependence of the band-edge PL intensity on temperature and excitation power density is also investigated. For the first time, the intensity dependence of upconversion trap PL on the pump power under two-photon excitation was obtained.