Instruct: Classify Amazon reviews into positive or negative sentiment
Query: hard

We have a colgate foam mattress for our oldest daughter that we got at buy buy baby, we love it. Then to save some money I found this one on amazon. And I'm really bummed out about it. Our one from buy buy baby is two sided, one side is for NB's then you flip it when the baby is 1 years old for a softer mattress. So when I ordered this one I thought it would be just like that. But its SO hard and its not double sided. We're using it for now, but I'm going to have to get something different our 4 month old just tosses all night in it, I feel like shes sleeping on concrete!