The rules (very loosely enforced, if at all) mention one carry-on bag and one smaller item (like a camera bag). The "smaller item" size is not defined, 14 x 7 x 10 may be pushing the boundaries. I only mention this because I once had the dreaded "C" boarding pass on Southwest. As I was boarding, the flight attendants announced the overheads were full and anything that did not fit under the seat would be gate checked. In that case you might have to choose between your camera bag or your carry-on bag.
Unless you are among the last to board this is not likely to be a problem, I have only seen it happen that one time but we usually fly in off-peak times.