Freaking out...

A week and 4 days ago I had my last progesterone shot, I'm 37 weeks and 4 days at 36 weeks my ob checked me and said I was 2-3 cm 80-90% effaced and baby is in position and ready to be born anytime....again still pregnant. Our son is measuring large 6lbs 11oz @ 34 weeks & 5 days while he measured 5 lbs at 33 weeks 1day. While I understand that ultrasounds can be off by a pound either way I've been measuring big since 28 weeks and previously had a 9 lb 6oz baby at 37 weeks after being told she would weigh a little over 8 lbs at 40 weeks, this is baby #4 and our only boy so its likely he will be bigger anyway, I have gestational diabetes and my grandmother had large babies over 8lbs 13lbs over 8lbs and a few oz shy of 15lbs the 13&15 lbs babies were boys and both stillborn. I'm starting to get nervous about approaching 38weeks I can tell he's running out of room, by his lack in movement and the fact that I've never carried this long. I'm really getting anxious & I know if I hit that 38 week mark I'm going to frankly be an absolute spaz. I don't really know what to, while I don't want to have a c section and I'd prefer not to have to be medically induced, my doctor doesn't seem to be concerned, I have another ob appointment the 16th, I've previously mentioned concerns about baby's size, he's been sure I'll be going into labor anytime. I'm just not sure what to do or how to keep myself calm. I'm sure this all sounds crazy to some of you, I can handle being uncomfortable, I can handle having to watch everything I eat and poking myself several times a day, but I can't handle the thought of my son being stillborn which has been a major source of anxiety since I found out we were even having a boy.