Well, these days, feminine motifs and designs are pretty darn popular; it's quite common to see ruffles on blouses and skirts, but it doesn't make it lolita. Sorry to burst your bubble, but it's true. Take a good look at the latest trends in office wear: ruffled top, pencil skirt, and heels (gosh, I'd love to dress more like this)
http://img291.imageshack.us/i/p5viky9.jpg/
Now take a look at an example of lolita (obviously, not all lolita coordinates are over the top, but hopefully, you get the idea)
http://cache.daylife.com/imageserve/08jL2SYgVmbZV/610x.jpg
If you're serious about becoming a better lolita, then it's best to learn how to differentiate, what is and what isn't lolita (that doesn't mean that you can't enjoy other fashions as well. I like classic New England prep, dolly girl style, and gyaru myself).
It's not "un-lolita" to mix ruffles with your jeans, but still, it doesn't make it lolita. It's just cute that's all.
What makes an outfit lolita, is how the items are put together, quality, and the infamous silhouette. My mind is a little numb at the moment, so here are two links to explain what I'm talking about.
http://www.lolitafashion.org/anatomy.php
The lolita community isn't going to put you down for wearing your favorite jeans with a lacy top. We've gotten pretty darn tolerant of this type of thing over the years (plus, most of us are in our twenties, so calling down on a younger lolita would be silly in our part), and many of us do similar things with our regular/every day dressing when we're not in lolita. The only thing we're likely to do is tell you to look into the memories (left side link on the egl page) or use the egl search engine (bottom left, box ), just because we get asked similar questions quite frequently and it's not a good idea to clog the main community page with similar topics. Just sayin'
All we ask for you to do a lot of research and try your best. If you stick to that, you'll get better. Everyone has to start somewhere. As your bloomers question: technically, yes, it's called underwear because you're wearing it underneath your skirt and petticoat, but it doesn't exist to replace your panties! Please, do wear your intimates (bra and panties)! Bloomers are basically shorts worn to keep prying eyes away from seeing your hello kitty panties when it's windy out or when you're going up the stairs. You can still opt for running shorts instead of the frilly pants, but I've personally found bloomers useful when wearing a lolita skirt because they protect my legs from my itchy petticoat, and they provide extra poof 8)
Anyways....have fun and keep learning.