What to do with my job?

I am so indecisive about leaving or not my job. Now i try to explain the situation: I work in the office and a 'm specialist of public relation. I found it very difficult because all the day in my office came so many people and all of them are angry. I have to inform them, explain, justify, help and calm down. I have to work 8 hours a day and than when i go home my little boy is waiting for me. He has his desires, wants me to do almost everything for him. This is normal and i love spending time with him. But i'm so tired (more mental than physically). I don't want to be nervous while i stay near him. In the same time i need my work. We are a family and we need money ( the life with a baby is more expensive then the time i was only with my man). There 4 years that i am doing this job. Do i have to wait and be more patients?!