Maybe break it down into smaller increments, that you can handle. I know if I look at the over all picture I get intimidated and start to withdraw. Maybe learn some stress relieving methods such as deep breathing exercises or other types of relaxation techniques. Check out and consider your learning style. Maybe you are trying to force yourself to learn in a manner that is stressful to you. Like I don't do well with lectures, just hearing something doesn't make things stick in my brain. I have to work harder at learning than say my daughter who has a great memory. I on the other hand have to write things over and over to be able to remember them. And I memorize by seeing what I've written.

Here is a link about deep breathing. It sure helps with anxiety once you learn to use it effectively. 3 Deep Breathing Exercises to Reduce Anxiety | World of Psychology