Did I make a mistake?

[Owlie]

Yes, there is a learning curve with road bikes. Give it another go and get used to the bike, then make a decision.

Your Ruby is probably geared differently from your neighbor's bike. Road bikes tend to be geared to go fast, so parts of the cassette (gears in back) are going to make you work harder than would a lower-geared hybrid (for example). I found that I had to build strength to use some of those gears. Shift down to the larger gears in the back and that should help. The stuff in your left hand lets you shift between chainrings. If it's a triple: Largest ring is for going really fast on flats or downhills (generally); I still haven't quite built up enough strength for it. Smallest one is for hills, and the one in the middle can do both, depending on what gear you're using in back. Many people (me included) spend most of their time there.

I highly suggest going to an empty parking lot. Ride around and play with the gears. You'll figure out what feels better on flat ground, then you can go on from there and figure out what feels right on climbs, downhills, etc.