What does implantation feel like?

Mandy • 29 years old - Married October 2013 - Mom of Baby Girl Dec 2015 😊 Expecting Baby Boy April 2018 ☺️
I'm 9dpIUI and I just had shooting/pinching pains on my left side. It would hurt then stop and then hurt again. This lasted maybe five minutes. Never felt this before. Thoughts?