My Nipples Are Completely Flat 3 Days Post Op. Will They Come Out when Implants Drop?

You are very early in your healing period. At this time there is a great amount of inflammation and healing that is taking place. Final results typically will take 3 to 6 months to realize. In that time the swelling will subside, the soft tissue envelope will have had sufficient time to accommodate thus allowing the implants to settle in behind the breasts. This will fill out the breasts and help increase projection.

Continue to follow up with your surgeon and be patient.This most likely will be transitory and correct in due time.

Best wishes.

Usually the nipples protrude more in your situation. I think you are still so early in the healing stage that you need to give your breasts 3-6 months to recover. I think if you are patient then you will find your shape will settle out a lot over time and the nipples might change over time. Only been a few days so take it easy and let the healing occur. 

It is too early to get concerned about your nipples...you are still swollen and your skin is under unusual tension from stretching due to the surgery.  Give yourself enough time for things to settle (several months) before scrutinizing your results.

Often with augmentation alone the areola will expand slightly and the nipple may become more prominent. The tension of a mastopexy can pull the nipple flat, though the situation is temporary for most as the nipple relaxes. Wait several months as things should sort out.

Nipples usually tend to protrude more after breast augmentation.  However, depending on the type of mastopexy, nipples may flatten out a little too.  You are only three days postop; your breast shape, areolar size/shape, nipple will change as implants settle down and swelling diminishes.  Try to be patient and wait at least 1-2 months.