An unexpected present

My mom gave an early christmas present today. It was a mouse priced at around 120usd. But the problem is I already have one, just have to change the cable. I told her that I don't need it but she was keen on keeping the gift. After repeated attempts to discourage her to change the product, we stuck with it. I'm still planning on changing to my old mouse when I order the cable. I really didn't want to make her feel bad, but still it hurts me know that the money went to waste. I'm not a materialistic person and it's not like we are a rich family. I see it as money going down the chimney. I'm writing this with a barely working 2$ mouse but it gives me pride somehow. Planning to cancel any Christmas gifts my way from now on. It just gives me anxiety.