Is my Peer score more accurate than my Self score?

Neither is more accurate. They answer different questions.

Your Self score shows how you see your behavior and what you intend. Your Peer score shows how other people experience it.

Because your behavior lands on other people, your combined score gives somewhat more weight to Peer responses than to your own. Peer scores also depend on who you invite and how well they know you, so a larger and more varied group gives a more reliable picture.