Hi, ladies, I just found this thread.
Poppy, what a crappy, scary day you've had - I hope you have a non-eventful night.
My DS2 is now 8 and entirely well.
We found out I had grade 4 PP at 25 weeks when I started bleeding at work.
I went to hospital, was checked out, (small) bleed had stopped by then, baby was well and was allowed home.
Big bleed the following day 
and I ended up admitted for the next 6 weeks. I bled several more times and he was eventually delivered by a very non-rushed and calm, but technically 'emergency' ie not planned CS at 31+3 weeks. He spent 5 weeks in SCBU, was ventilated for 2 days (a bit longer than expected at that gestation) and came home well before his due date.
FWIW, I only ever bled when flat on my back in bed, usually asleep. Apart from that first one at work (seated office job, so not exactly physically taxing).
I am of course not at all saying, do not rest, just that an element of good or bad luck is also involved.
As I bled several times with delivery threatened, I was transferred on 3 occasions because the hospital I was in did not have an availaby NICU cot during those nights (they did when he actually came along, thank goodness!). This ment, I saw far more consultants than you'd expect and the difference of opinionn was the most difficult thing to deal with: "Do not get out of bed, the nurse will bring you a bedpan when you need it" via "You can wander to the day room and watch TV" to "If it was up to me, you could go home and we'd see you for daily monitoring" 
- this was from a hugely respected, almost famous TV doc. It was most confusing tbh...
Very best of luck all of you. Sending Poppy sticky vibes, tell junior to hang on til 30 weeks if he/she can: do you know what you are expecting?