At this point you have to be patient and allow the breasts to heal. You may need to give it more time for all the swelling to subside. I would give it a good 4-6 months total at least, then reassess.
You need more time for healing....wait another 2 months and you will have a better idea of what size you will be. However, if you think they are big now you probably will feel the same way after another 2months...If you want to be a D cup it seems like you were a D cup to begin with and don't see why you would ask for implants. Best to wait and speak to your surgeon.
It is important to remember that cup sizes are really variable- there is no standard for sizing and depending on the bandwidth, depending on the manufacturer and marketing, your "cup size" could really vary.
Typically as swelling resolves and implants drop, the breasts do seem a little smaller. You could expect your breasts to soften a little over the next couple of months but not to "shrink" significantly.
All the best
I am sorry to hear about your concerns after breast augmentation/lifting surgery. Although I cannot help you with predictions in regards to significant breast size change over time, I can tell you that some changes can be expected. I can also tell you that your plastic surgeon has done a very nice job for you, with a relatively complex operation. In other words, you have achieved a very nice outcome.
If, in the longer term, you remain concerned about breast size, downsizing may be necessary; I would encourage you to exercise patience and evaluate the outcome of the procedure performed six months to one year after the date of surgery. Best wishes for an outcome that you will be pleased with long-term.
You are still early in recovery following breast lift with implants and your result looks very good. You can expect further decrease in size as swelling abates and you will have a better idea of your final result after 3-4 months.