If you try something too hard, a monkey, a roll or whatever and make it too frantic (verspannt). Then you use too much energy for this exercise and you stress certain muscles, which don't have to be used. So the exercise becomes hard and you lose your flow.
The solution for this problem is the active relaxation by each exercise you practice. Try to relax you body, don't be too frantic. Do it with ease and grace. So everything will become more fun, easier for your body und will also look awesome.