Beta hell and ultrasounds/Intro (long)

So I haven't posted here yet, since honestly I haven't really fully accepted it as being real yet.  It's just so overwhelming as if I am just dreaming.  My husband and I got our BFP on September 6th.  I use to post on T-TTC.  We had been through 6 treatment cycles (3 failed Clomid, 2 failed Follistim, and then our successful cycle, that was also with Follistim, but we had our second HSG to help with a small blockage and an IUI that cycle, we had been using TI before).

I really could use some advice if you have any, I think my situation is a bit odd, so if you don't mind I'll quickly walk you through the hell I've been through since my BFP.

On 9/6, which was 14dpIUI (LMP: 8/1, but stimmed late because of a large cyst, but since I don't ovulate on my own, we just waited for it to pass and then started.) I got my BFP.  It was negative in the morning, and since I knew I'd have AF in the morning I tested at night one more time.  I got a pretty faint line on a FRER.  About 2 hours later, I started to bleed, not cramping, just bleeding.  At the time I assumed it was definitely a C/P since it was bright red blood even with small clots.

The next day, I tested again to see if the test returned to being negative, but it still looked the same.  The next day I assumed for sure the test would be negative, but sure enough it was still positive.  I decided to go to the ER, even though I knew there was nothing they could do, to see what was going on.  They did an u/s and of course couldn't see anything yet.  They took a beta which came out to a mere 7.  I figured at that point it really was over.

Two days had passed and the bleeding had long passed (it lasted about 2 days).  I decided to take one more test and once again expected the line to be gone, except it was darker!  So, 2 days after being in the ER, I went to have follow up blood work with my RE, who of course was not optimistic at all.  The number came back at 10, which was way too small of a rise, not really even close to a 60% increase, so he told me to come back in another 3 days.

I showed up to my RE 3 days later, beta is now 18, again he says come back in 4 days.  The beta goes up to 44 and then 2 days later it was at 90, and the numbers were actually doubling within the 72 hours (very close to 72 however).  Over the weekend during the last test, he tested my progesterone.  He hadn't done it before in the cycle.  It ended up coming back at 0.94!  When I was actually on Crinone for the first 14 days and regular suppositories the next 6.  

So once again I don't know what to think, nothing about this pregnancy so far is pointing toward healthy.  I am on 2 suppositories a day and PIO (1cc/day), hoping to dramatically increase it quickly.

My nurse called me yesterday and says, well you should come in for an u/s soon and see how things are progressing.  This is where I really don't know what to do.   She says the doctor says I can come in this Friday or next Friday, but since my numbers will only be at about 450 on Friday based on my doubling times, there's a good chance we may not even see a sac (her words).   I looked online and it says that it should be closer to a 1000 before you can see anything.

I'm just so confused as to what to do, I really want to wait another 2 weeks, but I end up scared and crying all the time, it's been such a bittersweet time for my husband and I.  I just feel like I'm constantly waiting for the other shoe to drop.  

What would you girls do?  Would you go in this Friday to hopefully get peace of mind that something is actually there and it's not ectopic or would you wait the full 2 weeks so you're guaranteed to see something.  Since my numbers are so low, they don't coincide with actually being 6weeks today, my original EDD was 5/15, but with these numbers, I must have implanted really late. 

Sorry for the really long post, but I've been so nervous, I haven't even been the least bit excited.  Thank you for reading this!  I really do hope I get to stay here much longer.

Amanda