Stress is not inherently bad, however, when you don’t limit it and tackle it well, it can transform into distress, which can be unhealthy and difficult to go through. You need some tension and constructive stress to live well. After all, growth and antifragility come from struggle.
You become better and gain new skills and abilities by pushing yourself harder. The important thing to keep in your mind is to seek out challenges that are manageable and lie on the threshold of your skills. In this way, you apply considerable effort and push yourself a level up while still making sure that you don’t feel anxious and/or overwhelmed in the process.