What Is It?

Late yesterday afternoon, I saw a flying creature that I didn't recognize. It is larger than a hummingbird and shaped like a dragonfly with two outsized sets of wings, one set cantered forward and the other at right angles or slightly obliquely to the body. It lit in a tree -- not something I ever saw a dragonfly do. It did not fly as fast as a hummingbird but had a similar quick-turn flight pattern. What is it?