Have you ever looked at your workload and wondered why you seem to be getting all the work at your place of employment? You see your coworkers chatting away and going for frequent 'smoke breaks'. Yet, you can barely make time to have lunch, talkless to catch your breath.
Luke 12:48 - But the one who does not know and does things deserving punishment will be beaten with few blows. From everyone who has been given much, much will be demanded; and from the one who has been entrusted with much, much more will be asked.
Look at that scripture closely as it provides insight into what you might be experiencing. Could it be that your hands are blessed by God? Have you received a higher capacity than others to produce high-quality output and product? Could it be that your superiors have recognized that you are an outstanding employee - someone they can trust to do the work well - that they give you more?
From your perspective, it seems unfair and in fact, it could actually be. You could indeed have a boss who piles the work on You but fails to require others to work as hard as you do. You probably wish you were at least being paid more to reflect your increased responsibility. Most likely, your immediate boss didn't even consider a change in title.
Whatever the case may be, as a Christian, your remedy is prayer. Any complaints should be taken to the feet of the Father. Think carefully about what you want and use the word of God as your guide. Then, make your request. It is key, nevertheless, to not despise the extra work but instead to continue to serve at your job as if working for the Lord because of the instruction in Colossians 3:23. Just because you might be treated unfairly does not give you the right to break God's laws.
And if you are an employer with the sort of employee this post is speaking to, then you know you need to change. Remember that Joseph was a prisoner in Egypt but once Pharaoh recognized the hand of God on him, he was made the Prime Minister of the land. Joseph's position and rank immediately reflected his responsibilities.
Don't treat employees poorly. Reward them for doing good work. Failure to do so would be taking advantage of God's children. When the Pharaoh during Moses's time did this - using the Israelites as slaves and treating them badly despite their labor for his nation - he was visited with the plagues, the loss of his first son, and eventually death.
Matthew 11:15 - Whoever has ears, let them hear.