Reddit mentions of Prepac Sonoma Black Secretary Desk

You can do vintage/boho eclectic and mix it with minimalism to get the look you want. Vintage does NOT have to mean cluttery which is what typically produces that clausterphobic and cramped feeling you're trying to avoid. You're going to want to find and use pieces that provide organization and have ways to tuck away smaller things you need/use.

My suggestions!

Keep an eye out on craigslist for free or SUPER cheap area rugs, especially ones that have old-fashioned patterns, etc. Stick to one color (I think red would look super awesome what with your wall color) and put them on your floor, layering some edges if you must until the floor is covered.

For dressers since you said the room is small, you should consider picking one that can do double or triple duty. If you select a secretary desk dresser you'll get a dresser, a desk, and a shelf all in one piece of furniture and the look is very vintage. Even if you purchase a brand new one like this one, you can cheaply switch out the pulls for antique looking ones (look for brass either at a hardware store, or a salvation army/charity shop, or ask on craigslist or freecycle!) and use some sandpaper to rough it up. For a chair, I recommend a minimalist style of stool and for when you want your back to be comfy, use a lap desk and work from bed (assuming you have a laptop).

Utilize under bed space for storage and to keep your room looking clean. Buy flat containers and use them.

I looooove ILikeWhereThisIsGoin's bedroom ideas, but my idea for the bedside table is to locate or purchase a shipping pallet and with relative ease you can turn it into a wood bedside table that looks awesome and vintage and is also super cheap!

I love to use plants to decorate.. I use fake plants because I'm a black thumb, but IMO whether real or fake you should have some plants around your room. If you go with my secretary desk idea, I think some ivy-ish looking plants on the top ledge would look fantastic, as would something like a spider plant.

For art, you're in luck! Peruse salvation army stores, garage/tag sales, and check out craigslist looking for "traditional" art people want to chuck. You can either look for some big pieces or you can get a bunch of small pieces and make a photo wall arrangement on one blank wall as a sort of statement.

For bedding, if you utilize underbed storage, you need to have a bedskirt (it will also add to the vintage feeling). I think this one would look good, and then have white bedding (from the sheets to the comforter), and white curtains. Add a vintage-y throw pillow and then some sort of throw blanket or afghan (crocheted or knitted) for even more texture. HomeGoods is a good resource for this stuff (and anything decorative you'd like).

My final bit of advice is this and something I've learned having moved a lot and had lots of different spaces to experiment with interior decorating and design.. you need to approach items you're considering adding to your room as one piece of a much larger puzzle as opposed to just, "Do I like this bed? Do I like this pillow?" I know it seems silly but it's very easy to end up with a weird modge-podge of stuff that ends up just looking like American Basement more than anything or you end up with a bunch of stuff that all looks alike and is bland as hell. A pillow that, were it sitting in an empty room, makes you go "meh" may be the PERFECT pillow for your room because it works so well with whatever else you've selected. Some people never really get the hang of doing this (my fiance is terrible at this and thankfully he trusts me enough that I incorporate his style but do not get his input on most of the decisions and he's thankfully pleased with my results), some people it comes naturally to, and a lot of us have just had to really keep this in the front of our minds and train ourselves! If you have any friends who's homes/rooms/apartments are a style similar to your own or are even just well put together, consider getting their input (tell them what style you're going for, of course) when bringing it all together if you're not sure!