Big boobs really aren't as big an issue as the porno industry makes out.
In real life, a lot of guys really love small breasts just as much as bigger... Even had guys saying 'big boobs just get in the way'.
I used to think this was such an issue when younger but then I realised guys can find girls really hot even if they have little to no boobs, provided everything else is in place. Think about it, Keira Knightley has no boobs. I've seen hot guys swoon over flat chested girls before. I definitely think a worthwhile guy would find fake boobs a bit of a turn off, because it's unnatural and because there's literally no need for it. It also is just a dumb decision, in my opinion. That money could be a lot better spent, and all the people i know who've had cosmetic surgery weren't more confident afterwards. The problem is mainly internal not external.
I really doubt your face is as bad as you think. What features do you have that make you think it's so bad? If you want you can pm me and I can give you some advice about appropriate make up, because a lot of the girls in the U.K. plaster themselves in make up and it's actually really unattractive. Most worthwhile guys don't want a girl who looks like she's on her break from filming a porno film. It's embarrassing lol. You just need a bit of make up to bring out your best features, good skin care etc.
Others have suggested gymming for your bum, but actually you will find that eating well (super nutritious), drinking plenty of water, sleeping properly, and regular exercise gives you a rare glow. I always look grim during periods when I don't do these things, but when i do, I can see the effect all those positive body chemicals has on me, and feel a lot more confident.
It's actually really bad to be a girl today, because there's so many dumb expectations on how you should be. It's almost impossible to have a positive view of your appearance today - there are so many NON REAL photoshopped images of perfection, that we compare ourselves to, and the selfie/instagram culture helps none. Plus even if you have a lovely body, you're constantly getting messages it should be a different lovely body, if that makes sense. Skinny girls get shamed for having small boobs, but girls who have larger boobs probably carry extra weight in other places/can't be skinny... so it's like, impossible to have 'the perfect body' even if it's a lovely body. So I'm pretty sure almost every woman feels insecure about their body. Also, one of the best tips I ever received regarding appearance- don't compare your non done up self to someone else's 'done up self'. And definitely no comparing to photoshop images/ instagram girls.
Also, whilst I do get why being shorter may be difficult, I think you should think about it like this. You can't change that, so you should accept it. I remember there was one girl who would have been in your position in the past, because she was similar - lack of boobs and very petite. She said it really affected her in the past, being so small, and she still wished sometimes she had bigger breasts. But she found a really handsome and committed boyfriend who saw her beauty (inner and outer), and I suspect he also liked the fact she was small cause it made him feel taller around her. A lot of shorter guys (who can by the way be very handsome and charming) love to have a shorter girl. Seen it so many times.
I know it is really hard to be confident in yourself in today's society... but ultimately we're all struggling with the same thing. And it's a dumb struggle, ultimately a struggle of capitalism. Don't give in to the way the *******s want you to feel.