Baby pushing breast away while feeding - what does this mean


My almost 5 month old pushes the breast hesfeeding on or my chest and pushes his head away pulling out with my nipple lately - anyone else experience this ? I have had a strong let down but I thought we got settled into that cuz he wasn’t choking on it coughing on my milk anymore and wasn’t coming off screaming like he did as a newborn.

He use to put his hand on my breast while feeding and then would play with my shirt or strap. Now he pushes off so hard - anyone know what this could be?