baby psw dependant visa refused

I have PSW visa and came to Pakistan. I am here for one year now due to sickness of my mother in law. when i intended to visit to uk i applied for my son's visa. My son is 3 years old and born at uk. I have bank statement from both uk and pak bank accounts. I work here as university lecturer at pakistan and have shown it. they refused my son's visa by stating following

You must be at uk as you have resident permit for it and why are you working at pak? Further they question the source of money in my account at pakistan besides the fact that i have this money there for a year in my account. They even did not give me right to appeal. What can be best thing for me to do now?
i dont know if there are any conditions for psw that they must stay at uk and that they cannot work in any other country for some time during this time.