What is wrong with my breast implants?

You are "too large" with 450cc implants, which are generous but not huge implants. You did not show pre-op photos or give pre-op breast size, nor do we have your height and weight. "Too large" is certainly in the eye of the beholder, and it appears as if you had some degree of ptosis in addition to having at least a bit of your own breast tissue, leading your surgeon to recommend above the muscle, to better "fill" your loose skin brassiere. Right? You obviously needed a certain volume to adequately fill the loose skin that you possessed, so "too big" is a result of trying to avoid the incisions, scars, and cost of a breast lift which would have reduced and tightened your skin "brassiere" as well as permitting smaller implants without "rock in the sock" look. Judgement call, but without being there, it is impossible to know if it was your surgeon's "call," yours, or a proper bit of both.The problem with above the muscle implant placement is bacterial contamination from ductal bacteria, leading to biofilm on the implant surface, causing stimulation of capsular contracture (more on left than right, leading to "hurt when I lay on my stomach, especially the left one.") By your description, you have capsular contracture (CC) on the left side, and possibly to a lesser degree on the right.So, in the absence of better pre-operative choices or more discussion of the pros and cons of the choices made, yes, you need a revision. No sooner than 6 months post-op would be my recommendation. This procedure needs careful consideration and much discussion--should you keep the same pockets and the high(er) risk of recurrent CC, smaller implants with more skin laxity and droop, or smaller implants, breast lift, and new submuscular implants? If the latter is the choice, then you have a subcutaneous (breast lift) surgical plane, a previous above-muscle (below breast) implant plane (and what provides blood supply to the breast in between these surgical planes now?), and yet a third surgical plane below the muscle for the new smaller implants.Many surgeons, myself probably included, would likely feel "forced" to use the same above-muscle plane, leading to a higher risk of recurrent CC, to avoid possible dead tissue by having all three surgical planes without adequate circulation.This is why it is important to make the first operation the best one with the best choices. Not preaching, just trying to educate other prospective patients reading about your problems, all potentially preventable by better discussion and choices before. And why your second surgery needs to be the best one possible--this is not an easy "chip shot" revision.At this juncture, you need to interview several experienced ABPS-certified plastic surgeons who are also ASAPS members and do lots of breast surgery (along with the concomitant revisions). Best wishes! Dr. Tholen

you don't say how long ago you had your implants inserted. Sounds to me that you should have had an augmentation mastopexy with smaller implants. If the left breast is misshapen and hard it may signify you have a capsular contracture. 

If they are too large and saggy, then a revision with smaller implants and a lift may be indicated. Especially, if there is painful hardness, a capsule may need to be addressed as well.An exam and consultation with a plastic surgeon is recommended to discuss your options.