According to Osho, if your “witnessing” feels tense or sickly, it isn’t witnessing at all but ego-based self-consciousness. True witnessing is relaxed, egoless awareness. Begin as Patanjali suggests: first concentrate on the object (dharana), forgetting yourself; next, drop the object and notice only the fact of watching. Only then does authentic, subjectless witnessing flower; otherwise meditation becomes another ego-disease.
If watching yourself feels tight, you’re in your ego; instead, calmly look at something, then feel the simple watching and let the “me” drop away.