Oblomov - I'm really sorry to hear that you were so badly treated at the hospital last night. I think that whoever saw you while you were there should have at least offered some kind of explanation or guidance and it's utterly crap that they didn't. I think that when you're not getting the service you want or need, you have to be awkward and ask question after question until you get some kind of response at least. I know that's not going to help you now, however.
You also said "What exactly do you all think is going to happen, that will give me any sort of reassurance today ? I don't understand why you all think it would help. You all know that they will tell me that they can give no assurances. You all know that they will tell me to try and relax until 7 weeks."
I honestly think that everyone who responded to your posts, myself included, only wanted to help or support you in some way. We can only offer you advice and comment on our own experiences in the hope that it will help you. There's nothing concrete that any of us can do from our positions to give you an answer one way or the other.
You're right that EPU wouldn't be able to give you any guarantees or cast iron assurances - they can't do that for anyone. When I went to my EPU last week, I was told that even though a heartbeat had been detected, it was no guarantee that the pregnancy would continue and that if the bleeding continues (which it is), that I should view it as a threatened miscarriage (which I've been trying to push to the back of my mind in order to stay positive). It's absolutely horrible and awful I know, but there's nothing anyone can do for me. I just have to sit it out and wait to see what happens whilst hoping beyond hope every day and staying positive. I won't get another scan now until I'm about 12 weeks, so I've got another 5 weeks to wait and "try and relax", which is exactly what I will do.
Do you have anyone that you can talk to about how you're feeling? Would your DP/DH be able to spend some quality time with you and are you able to talk about it together? Have you talked to anyone about how you felt after your last experience? I'm just thinking that you've really been through the mill and have had a traumatic experience - it might help if you can talk to someone close to you. Have you looked at any of the 'knicker-checkers'/pregnancy after miscarriage threads? There will be lots of ladies there who will know just how awful things have been for you and who will have had similar experiences - it might help to talk it through with them.
I think that everyone here will also be happy to continue sympathising and supporting you in whatever way we can - that's what these ante-natal threads are for, I think. We might not be able to give you definitive answers or cast iron guarantees but we can listen and offer our advice (however helpful that might be).