If you are surrounded by people who shout or scold you in loud voice, then this reaction is quite obvious, as I assume that you are not in a condition to protect yourself. You are a field officer and your job seems to demand constant hearing from supervisors or seniors and taking commands or instructions. In such conditions, it is not easy to defend yourself as you are helpless due to your employment and fear losing job. This makes you vulnerable to remain submissive and docile. You need to be more assertive to resolve this. In many such cases like yours, seniors generally make unrealistic demands and expectations to do work perfectly and in time. In order to make yourself comfortable and adaptive, you need to tell straight what you are capable of doing and what not. If a certain task requires time then say clearly about your capacities. Dont hesitate to put your words into action.

This trend often indicates low self confidence. It is basically due to low self esteem. Kindly consult a clinical psychologist at your place who can better guide you to deal with this issue.

It is because,  you have not learnt to say NO. Maybe,  you had been told,  that you should respect others,  you should not hurt others feelings,  and all that. In the meanwhile,  you would have started believing that being given good is the only factor,  to be liked by everyone. The more you learn to practice to say and do what you wanted,  the  enter you become.