Doctor told me I needed the flu shot..

She told me because I'm pregnant I needed to get a flu shot, but I haven't had one in years. I didn't get it when I was pregnant with my son and he turned out perfectly healthy. The only time I've ever had the flu was when I got the shot,I never really get sick and when I do it's just a cold. I had walking pneumonia once a few years ago and that's it. Do you think it's necessary to get a flu shot while pregnant or in general? Pretty positive I'm not going to get one.