Mastopexy and reduction mammoplasty (breast reduction) terminology can be confusing. First, its important to know what size you currently feel you are at.. C, D, DD, DDD? You specified you wanted to be a C/D but not sure where you are starting. If you are wanting to downsize then by definition you are wanting a reduction mammoplasty. You get a lift with a reduction just by the technique used to reduce the volume. However, a mastopexy or lift is just skin excision with tissue rearrangement (not much removal-very minimal, maybe 1/2 to 1/4 cupsize and often times even less than this. Women who come in wanting to stay the same size but just wanting the nipple and areola lifted and the breast footprint higher on the chest wall are scheduled for a mastopexy. Women who want a reduction in volume by more than 1/2 a cup size are scheduled for reduction mammoplasty which includes volume reduction and a lift.
It sounds like your concerns are coming from pain that began in the right breast and is worsening/spreading. Did your plastic surgeon order the MRI? MRI is gold standard to look for implant integrity or rupture with a greater than 90% specificity and sensitivity. The radiology read will report whether the implant is ruptured or not. If it is ruptured the read will also comment on whether it is contained in the capsule (scar tissue around the implant) which is intracapsular vs outside the capsule (extracapsular). It is difficult to interpret the photos here as I'm not a radiologist but they look for something called a linguine sign (lines seen where the shell collapses compared to the capsule or scar tissue around the shell). There are other signs as well that may show better on other images not included here. Pain can be from many things including capsular contracture (increasing tight feeling of the breast) that can sometimes only be felt on exam but when progressive can be seen as well on visual examination. Pain can also be caused by implant displacement, implant rupture and things unrelated to the implant, which could be breast related. You should return to your original plastic surgeon or other plastic surgeon specializing in breast surgery to further discuss the MRI read and for a breast exam to look for other pain etiology if implant is not ruptured.
Most surgeons who perform cosmetic breast augmentation also perform body contouring procedures such as abdominoplasty (tummy tuck). Sounds like you had a good experience with your previous surgeon and its been 13 years so this surgeon has experience as well. Its always a good idea to get your implants examined as they are aging and at this visit you can ask about the tummy tuck, explore pros and cons of the procedure and be sure you are a good candidate. The surgeon will discuss the excess tissue and likely examine the abdominal muscles too to see if they are in need of repair/tightening. You may choose to see another surgeon for a second opinion and see if the plans are similar or weight out the risks and benefits of each approach if different.