As for the saggy breasts, most of the women who do porn have fake breasts. you can tell that they have had them done after you see a really obvious badly done one. Also they lie or pose in a particular way so that you can't tell that they are saggy, normally with their hands above their heads or behind them and their chest pushed up. I don't know if it is appropriate to link to an example so i won't.
You can do push ups and it will help a little bit to make them more perky looking. also if you have stretch marks on your breasts you can use cocoa butter on them. if you use it five times a day they will fade in about 6 months to a year. just take a jar with you and apply it when you go to the loo. It also makes your skin look really nice.Also wear a nice bra, if you have big boobs like that I expect you wear a DD or E cup or bigger which is difficult to find in the shops.
About your nipples, you can use the cocoa butter on them too. but if you have large breast you will have large nipples and when you get cold or turned on, they will look all crinkly like that.
About your labia, there is not much you can do about that. you can do squats and and the kegel exercises that tightens up the area and they will go in a little bit, so its a lot less noticeable and won't stick out as much.
About surgery, just to remind you, they cut you with a knife and it leaves scars, especially on your boobs. Also not all surgeons are good or sane or do a good job all the time.
About your self image, you need to stay away from one night stands, if you can. Make better friends with your existing friends, it can take a long time to find a good man and you will need them to call on! Wait until you can find a good man who knows you aren't perfect but loves you anyway. One who will not go on and on about things that make you feel really insecure even if he is really, really, angry with you.
About your insecurity, you need to be on the look out for ways you can improve your self image, and I would recommend that you go out and do things that you enjoy so you can cancel out the bad feelings it is generating.
Good luck

and remember doctors, especially plastic surgeons are greedy, money grabbing b****** who prey on your insecurity to feed the luxuriant lifestyle they lead. (just joking, not all doctors are like that, just plastic surgeons)