If you don’t look back at your old work and cringe, at least a little, you’re not learning enough to keep yourself moving forward.
It’s absolutely a common thing, especially in fields where creative work is part of the job. All we see are the flaws and the ways we could have done better. In our minds, the strength our work is minimized, and the flaws magnified.
The fact that the pace of the problem is picking up for you is simply a reflection that you’re learning more in your professional life, which is great!
@dopamino, as always, has some excellent suggestions on how to learn from old designs. Definitely follow his advice.
Personally, my approach is to occasionally revisit my past work and write down what I did well, and where I could have improved. The act of writing it out helps me absorb the lessons, and forcing myself to see the positive aspects of my work helps me focus on how my strengths as a designer have grown over time.