Not enough info so far to give much useful advice beyond what Mt. Spokane offered. but one thing I've learned is never to take off on an important vacation with a brand new camera. I have sometimes needed a thousand or more exposures to figure out how to use a new camera body, even with my old lenses.
I am just learning to use my 40D right and get the most out of it - I bought it in 2008 ! O.k., I am no professional shooter but I do reflect what I am doing deeply and have some extended knowledge about technical details of photography, electronics, etc. (as every physicist).
For me it is a joy to use an instrument over half a decade or a decade because I learn to master the tool - instead of being masterd by the tool ...