Am I Wrong for Kicking My MIL Out of My Home after She Came over to Do Me a Favor?

I sank into the couch, exhausted, as Emily’s cries echoed from the nursery. Three months in, I still didn’t know how others managed—colicky baby, two hours of sleep, and somehow, looked put together.
Peter called earlier, asking how we were. “Surviving,” I said. “You’re lucky you’re not stuck here with this little tyrant.” He suggested his mom, Melissa, come over to help.
Reluctantly, I agreed. Melissa arrived the next day, but she quickly criticized my appearance. She took Emily from me and told me to rest. I warned her about Emily possibly fussing, but Melissa assured me everything was fine.
I woke up to Emily’s cries, but when I checked, the baby monitor was off, and my phone was missing. I found Melissa outside, on the phone with Peter, ignoring Emily.
I confronted her. She’d unplugged the monitor to “let me rest” and took my phone outside. I was furious. “You left her alone for thirty-seven minutes?” I yelled. She dismissed it, saying I was overreacting.
In a snap, I told her to leave. “I don’t trust you with Emily,” I said.
That night, Peter came home. I told him about what happened. He defended his mom, saying she was just trying to help. I was frustrated—he was more concerned with her feelings than what she’d done.
Was I wrong to kick her out? All I knew was that Emily deserved better.