So many questions - Help

I only went to the doc once so far (at 9 weeks) and am currently 12. My next appointment is next week and I cannot get through to anyone. I opted to do the NT Ultrasound (at 13 weeks) along with the Cell-free DNA screening. I had 4 viles of blood taken at my 1st appointment in which one was from a kit by Natera. . I just want to know when I should expect to learn the gender (along with other things of course) but hoping you guys can help. Also, what is the difference between NIPT & NT?