Hi there, emichele. Congrats on a great bike choice! I have a Quick 3, which I love. The Quicks have a lively yet smooth, comfortable, and pretty fast ride for a hybrid. They are light. I don't think you're necessarily on the wrong size frame. I'll tell you why by telling you my experiences in buying this bike.

I went through quite a bit of second guessing on frame sizes too. I'm a bit taller than you, 5'6", and I ended up on a women's tall. I thought at first I might've gone too large, but it is perfect. I thought the medium would be okay, as I had several shops assure me they could fit me to a medium. And I'm sure they could've, somewhat. The shop I bought from, who has a very good fitter, convinced me to let them build a tall for me. At first ride it felt too large, but the more I rode it the better it was. I now feel that it's perfect. We set it up with a more forward, aggressive position, as I wanted it to be my flat bar road bike. A year later and I'm ready to go roadie. Can't believe I got comfortable in a forward position!

If you have longish legs, the medium should be good. Cannondale Quick frames are women specific; that is, they have slightly differing geometry than the men's. But the medium frame only comes in the unisex version, not WSD. As I said, I'm only 2 inches taller and I'm on the next size up. If, however, you have short legs then the women's small might fit you better. But at 5'4" you probably don't need a small. The shop you bought from should be able to size you and set you up comfortably. Yes, you can raise the height of the handlebars. But rather than trying to get more upright like your old clunker, why not try to get used to a bit more forward position? You'll get better results from the energy that you put in, and soon you may be asking for that bar to go lower!

It takes a while to get the saddle adjusted to your liking, once you start putting some miles on it. If you don't feel it's right get yourself a multi tool and play around with it on a ride. Try tilting it up, as often shops send the bike out with the saddle nose down (men!), and try it a little more forward or back. A year later and I'm still adjusting my saddle. And I've tried 3 different ones trying to find one that's just right. You will find many threads on here about "what saddle" to use. Just keep in mind that if you're riding upright a road saddle will not be the right shape to support you where you need it. And they come in widths to fit your sit bones. The wrong width can cause pressure points too.

Good luck, I hope you find out that you do have the correct size, because you should really enjoy riding this bike!