Which is the real character level in Rift?
Your real character level is 18, but you have mentored down and your effective level is 10. At level 15, you got a quest that taught you how to mentor down, so that's probably why you're 10. Certain areas, like nightmare rifts (with all the eyeballs) also automatically mentor you down.
You can clear your mentor level by right-clicking your portrait.
Also by right clicking your portrait, you can choose to enable sidekicking. This will increase your level, up to a limit per zone, when you group with a higher level player.