Mom being manipulative?

Spent the weekend with my mom and she took my phone away for a month. My brother is my guardian and he just agreed to it and gave me a flip phone for the meantime. When I had a visit with my mom I mentioned to her how I’m excited to get my phone back and I’m counting down the days, just sharing my excitement that’s all. Then she made a remark and said you’re not getting it back anytime soon. But our deal was one month and we had a certain date i was getting it back. But now she said cause I said I’m excited it shows that I’m still obsessing over my phone. I also overheard her talking to my brother about it.

Is she being manipulative?