Lanez, 28, hasn't commented on the allegations.
Megan claimed she didn't tell LA police the details of the shooting as she feared for her safety and was afraid of legal consequences.
"I didn't tell the police nothing because I didn't want us to get in no more trouble."
Police officers were in attendance at the time, as she revealed police drove her to hospital where she had surgery to remove the bullets.
According to police and prosecutors, the case is still under investigation.
Megan said a fight broke out when she was sharing a ride in an SUV with Peterson and others.
She claimed Peterson shot her when she tried to leave and brushed off rumours she had hit him in the vehicle.
She said she was "extremely grateful to be alive" following the "traumatic night" but that she was "expected to make a full recovery".
Megan said the surgery was the "worst experience of my life" and "super scary".
"Why would I lie abt getting shot? Why are y'all so upset that I don't wanna be in the bed sad? Why y'all upset that I can walk? I got my stitches out my feet like 2 weeks ago and I was ready to go celebrate WAP going number1…"
Amid recovery from the shooting, Megan is enjoying huge success after featuring on Cardi B's song WAP, as the X-rated track hit number 1 on the Billboard Hot 100 this week.
She's also nominated for artist of the year in the upcoming MTV Video Music Awards.
Sky News has approached Tory Lanez for comment.
