Congratulations on your first match.
I see a lot of M&Ps around here. When they first started using them around here in IDPA, they were getting 10 round mags to use for slide lock reloads because the 17 rounders were causing malfunctions when they slammed the reload.
Somebody else mentioned, maybe take a little off the bottom of the follower to allow it to go a little deeper into the mag body.
Run the gun you have for now. I used to shoot against a buddy who is a better shooter than me. He was doing the gun of the week for a while and I could beat him.