Anyone else feel like they'll be pregnant forever?

This is my third baby, and I have been 4 cm dilated and 50% effaced since 31 weeks. I was put on bed rest until I made 35 weeks and now nothing has changed...well except the size. I'm 37 weeks and measuring 41. I had an ultrasound today to get an estimate of his size and he is measuring 8 lbs 12 ozs!!! Holy moly! I know ultrasounds aren't always accurate, but all of my kids have been big and the ultrasounds were pretty spot on. And let's also add that his head alone is measuring 41 weeks 2 days. Lord help me!