How does an unmarried woman distinguish between semen and the yellowish vaginal discharge resulting from infections, especially when seeing or touching something that arouses desire? And how does she recognize the signs of semen, such as languor, a feeling of pleasure, and its thinness?

If you are certain that semen has exited, you must perform ghusl (definition) (ritual bath), and its characteristics are explained in Fatwa (definition) no. 102977. If you doubt whether the discharge is semen or ordinary secretions, you may choose and assign it the ruling you wish; see Fatwa no. 118035. Yellow discharges are impure and must be purified from; see Fatwa no. 125407. It is advisable to disregard whispers (waswas) and avoid anything that incites lust.