Congratulations! The first time I had a hummer I was practically stunned, and was afraid to move!
Mine are more active after 6pm as well. My first sighting a few years ago was at 7:45pm. My female was recently there at 8:30 the other night, I guess getting in every last sip she could! Despite having plenty blooming for the hummers now, they still prefer my feeder, although I did catch the male checking out the Penstemon eatonii and the female hitting the annual salvia in the window box on the deck railing...

You will find that they are up early in the morning too. Mine show up at the crack of dawn before the sun is up - this morning I had one at 5:14 a.m. I believe they need to fuel up before going out to hunt their main diet (insects) and will tend to be active early in the morning, sometime just before noon, and late in the afternoon and into evening through until after sunset. The rest of the time, they may be perching and defending territories. Once the babies hatch, you may see more visits throughout the day.

I, too, saw my first hummingbirds this year. In early May, when it was still quite chilly in the morning, I saw a male. There's no mistaking what you're seeing, with those gorgeous irridescent green feathers and ruby throat. I couldn't have moved if I'd wanted to. He peeked at me over the balcony railing like a little helicopter rising, hiding, then rising again, just inches from my face. Then there's that low pitched whiring sound their wings make, absolutely amazing. Right now I only see females, no males. Based on their shapes, and from which direction they come and go, I believe I've identified two. There is now possibly a third, a wee, tiny thing that is so small she doesn't perch on the feeder, just hovers when she feeds. I guess she can't reach. Isn't it wonderful how joyful these little birds make you feel.

Congrats! It seems that the first time you have the good fortune of a visit, it's a mesmerizing experience. Not that subsequent visits are any less special of course.
We also had our first encounter last week. After being inspired to create some sort of hummer-friendly space after our visit to the Arizona Sanora Desert Museum last winter, I was beginning to wonder if my work had been in vain. Then, as I was out weeding in the afternoon, I heard what sounded like the biggest bumblebee in the world beside me. Somewhat concerned, I turned to see a very large ruby-throat hovering in front of the coral honeysuckle vine. Shortly after it left, we were visited by a much smaller, bright green ruby. It stayed for several minutes, feeding on the honeysuckle, cardinal flower and various salvias we've "installed."
Here's to more visits and further encounters with the little winged wonders!