Difference in quality of the overall works I finished.

While I look through this site, I can find a huge difference in the quality of the works I have done past years. The artworks I've done during 2013-2014, I had more time to work on each piece compared to the works I did in 2015. Because I was a high school student I had more time and no due date, I took 3-4 weeks on each of the works I made. However, since I came to college, I had to finish my artworks before the due date which was usually a week. This is the huge reason for the difference in the overall quality. I guess I will have to find a way to make my work look better.