I think some good questions to ask yourself are:
"What do I want from my relationship?"
"Is this relationship, as it is right now, good for me?" [If yes, great; if not, then why not? What would have to change?]
"Am I able to freely express who I am and what I'm about in this relationship?"
"Am I able to get what I need from this relationship?" [If you are, great; if not, then how can you make sure you do get what you want?]
"Why did I agree to a polyamorous arrangement?"
"How will polyamory benefit me?"
"What are the pros and cons of this polyamorous situation, for me?"