ENFPs can be quiet and not very social when depressed or stressed. Best way to tell if you are ENFP or INFP is if you lead with Ne. In most cases this difference is quite obvious. While INFPs have reasonable use of Ne, they don't normally use it like nutcases (see ENxPs). ie. if you seem to keep that intuition under wraps and look strangely at people who go on endless tangents, you are probably INFP.