Philosophical stance

Like a horse at a big jump, I'm stalled. For over a day, I have not written the ten paragraphs I want to write about my research philosophical stance, in my methodology chapter but have considered

• realism
• constructivism (what's the difference between constructionism and constructivism?)
• positivism

I had argued myself into believing I was taking a constructionist approach because I was seeing my informants as constructing themselves in the context of an IT project, that they constructed their relationships and how they engaged with each other. But now I think I'm taking a critical realist research perspective because although the organisation's IS project development took place in real objective space, each individual participant constructed them selves in a particular way in relations to the project or programme setting. That is critical realist, isn't it?