Sounds pretty normal to me! Keep in mind that you can't estimate a baby's weight accurately before it comes out. Sonogram estimates aren't even reliable.
At my 36w ultrasound (a few days after 36w), they estimated 6lb7oz. He was born at 38w4d, weighing 7lb6oz. If he'd gone to 40w, he'd probably have been just over 8lb... so a good size, but not huge
Re: 36 weeks baby weight
to be 7 lbs. He was born at 35 weeks and weighed 6 lbs 15 oz. So somewhat accurate..