I got this gap after I got my braces off? (Photo)

I had my braces in for about 1year and a half, and my teeth were perfect, they were like i wanted them. Then a few days later i started noticing a gap in between my front teeth. It was barely noticeable, bt after a while i felt like it looked bigger. I went to my orthodontist some time ago and she told me that it was normal, but i didnt think so because i didnt have that gap in before. Is it actually normal, or am i just being paranoid?( i wear my retainers everyday, except when i eat)