3 wk post op, I am worried that my nipples will permanently be facing downward at the bottom of my breast and not in the middle.

I note from your pre op photos that the breast skin below your nipple is quite short and tight. This will take up to 6 months to stretch out and for the implants to drop. At such early stage after surgery, the swelling above the nipples also accentuate the fullness in this area. All these should improve over time. All the best.

You are very early in the post operative period still. It can take 3 or more months for your body to adjust to your implants. Your surgeon may recommend displacement exercises and or a breast strap to help your implants drop. Discuss your concerns with your surgeon at your earliest opportunity.

Thank you for your question.  You are very early after your breast augmentation and your implants should drop and assume a better position beneath your nipple areola.  As the implants drop the nipples should be projected forward and as the implants gets below the nipple areola your nipple position should look much better.  Of course consult your plastic surgeon and ask if breast implant displacement exercises may be of help.