Stabbing Pain and Urge To Push?!

38 weeks and 4 days here.. I have been noticing multiple random changes this past week or so, but today is the biggest! I slept all day because of course I didn't sleep last night.. but when I woke up, I was feeling crabby and like I got hit by an 18-wheeler. I have peed A LOT today and pooped quite a bit, too. But the scariest part was about an hour and a half ago when I went to pee and as I was finishing, I keep feeling this sharp stabbing pain in my vagina and a very slight urge to push! The pain is not in my cervix, it feels like it's in my vaginal walls. The overall feeling of both feels as if I have a tampon in the incorrect way. Is baby making his appearance soon?! What is going on?! I have my 38/39 week appointment Friday..