Ask yourself these questions:
Do you love selling?
Do you love your product or service?
Do you love your company or business?
Do you love working with your customers?
These are not silly questions, they are questions that can affect your performance or productivity, including your attitude and income stream. Too many salespeople fail to come to grips with why they stay in their present job.
If you do not love what you do and do not reek of enthusiasm and passion you will do no-one any favors by staying in that chosen field.