The salary you are offered is about there for hospital with your experience.

Salary is better at the retail setting as you can/required to work extra hours at locum rates which is 25 - 30/hr.

On average, retail pharmacists can fetch home about 4+k, 6+k with longer hours and weekends burnt.

The reason why sg has shortage of pharmacists is, 1) no prospects, 2) low pay, long hours, 3) no respect from doctors/nurses/patients.