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They are so small. According to the measurements you're supposed to take to figure out your cupsize, mine don't even qualify for one. The instruction is that for AAcup you should have about 11cm difference between the numbers. Mine doesn't even cross ten, or nine, or, well I'm not going to continue this. Anyway. I hate my boobs. They're so small and they are ugly. I look like an overweight pre-teen boy with saggy nipples. Ok, part of this is true. I do have so baggage to drop, and maybe if I got rid of that they might look decent...but still gonk
It's not like I want huge Pamela Anderson like bumpers. I'd like them small, but not so small that one has to use a magnifying glass to find them.

Since you're stuck with what you have you could always work out to even out your body to be on the slender side? Or who knows maybe you can put more emphasis on dem hips or dat a** to compensate.

Literally all of my friends have C's or greater. I used to feel incredibly flat too until the lady at Victoria's Secret told me I was the most average and common size.
In middle school everyone in gym class would have bras and I would be all 'but I don't need one why do I have to wear it =|' and then change in the stalls all the time.

Could be worse. You could have missile tits.

The company I work for makes a cream that suppose to make your breasts bigger.

Also going on birth control can make them bigger.
... Or getting pregnant.

Department stores usually screw it up, so your home measurement will probably be the most accurate.

How many inches are you adding when you do the underbust? I shoot for like adding only 2ish. Department stores will add like 4, which is horrible. A lot of websites tell you to do the same, so you might want to try again but this time don't add too many inches, if you did. You could theoretically come up with a couple bra sizes, like what it would be if you added 1 inch, if you added 2 and so on, so then when you go shopping you'll have a good idea of which sizes to grab in the fitting room.