"Wednesday The 13th??!!"

I have never missed a single appointment in these 37 weeks of pregnancy...I was late for a couple but had informed the clinic, well in advance.
& yesterday, I missed the u/s appointment!
I got up @9am, realizing I needed to check what day appnt was on(wednesday or thursday)..
9:10am, it had completely slipped my mind!
@10:58 am, I realized I had not checked for my appnt only to realize that I had missed it. The appnt was @10am!
I am feeling so miserable...how did I forget such an important u/s appointment? What was I thinking or not thinking. This is the most important u/s(@week 36) that I need to take...
I called up to reshedule - the next available u/s appnt is only on the 26th(ie around week 39)!
Called up the Doc & she was not happy to hear I missed the u/s; she is going to try to get me in - if she can..:(
Hope, I get to see how Tweetu is doing, in the next coupla days...
UPDATE: The doc managed to get me a stat(emergency) u/s appnt. on the 14th. The 45 min u/s went extremely well. The Radiologist could not locate my Cervix. Hence we went ahead with 'internal' u/s which was thankfully better than what I had expected! The amniotic fluid volume is within the range of normal with an AFI of 11.7 cm. Normal cervical length & a posterior placenta with no evidence for previa were observed. Tweetu's estimated weight in grams was 2495. Although the
composite estimate of her gestational age was noted at 34 weeks 5 days, the OB mentioned that there is a standard deviation of 17 days which puts her back to the 36th week with no change in the EDD.