Almost 5 month old EBF

How often is your almost 5 month old eating during the day? We started solids about a week ago and just yesterday went to 2 oz of pureed food 2x a day, before that it was just 2oz once a day. Lately when my little guy is nursing, he pulls away and gets mad after 2-3 minutes and when I try to burp him he starts sucking on my face like he's starving. I put him back on the boob and he will eat and when he's totally done, seem somewhat satisfied. Any ideas on why he's acting like he's starving? He is nursing about 6 times or so a day.