When will my nipples stop being erected or will they stay like this forever?

At this point in your recovery, it is much too soon to be worried about the outcome.  It takes time for the implants to settle into position and the skin and muscle to stretch out to accommodate the new implant.  It may be 6 months or more before the shape has reached its final look.  Be patient.

It is very common to have complaints of nipple sensitivity and even erection after an augmentation. The nipple has been pushed into a more prominent position and needs time to adjust to the new stimulation. This should resolve in a few more weeks.  Good luck.

You still are early in your healing process and still have swelling. As the swelling subsides, hopefully your nipples will settle back down to normal.