Today was my 34 week check-up. Up until this point all of my appointments have been really easy and baby has been measuring right on schedule. I also have been gaining weight right on schedule (after my 1st semester larger than normal gains).
Well, today was a different story I gained 4 pounds in 2 weeks and my baby went from measuring right on 32 weeks at my 32 week appointment to now measuring 37 weeks at my 34 week appointment.  This didn't come as a shock to me because over the past week I had my mom and best friend in town. I was eating out most days, I hosted a bridal shower AND baby shower over the weekend so I was eating and eating and eating.  The cakes and brownies were just too good to pass up.  Well, I certainly learned my lesson!
  I gained 4 pounds in 2 weeks and my baby went from measuring right on 32 weeks at my 32 week appointment to now measuring 37 weeks at my 34 week appointment.  This didn't come as a shock to me because over the past week I had my mom and best friend in town. I was eating out most days, I hosted a bridal shower AND baby shower over the weekend so I was eating and eating and eating.  The cakes and brownies were just too good to pass up.  Well, I certainly learned my lesson!  
This then prompted a need to schedule a growth ultrasound which I guess isn't so bad seems how I haven't had one since my anatomy scan.
The other thing though that has me worried is when they did the Doppler to listen to the heartbeat there was an obvious irregularity. My LO was missing beats and although my MW assured me that there should be nothing to worry about she did make certain that during my growth scan that the also do a echo cardiogram. She said that this was not an emergency and that she will do both at my next appointment in two weeks.
I am not going to worry too much (easier written then done) and be happy that LO is at this moment doing a gig in my belly so she must be doing okay! 
Re: Oh MY! (long)
I was measuring large as well (measured 26cm at 24 weeks and 32cm at 28 weeks) and had normal weight gain so did a growth ultrasound also. After way too much googling what measuring big could mean, turns out baby is just nice and big. My doc said the same thing...babies have growth spurts and it's usually nothing to worry about.
Don't worry! (yeah right) and for your own sake don't go looking up everything bad that could possibly be going on. If your midwife isn't worried you probably shouldn't be either. Hang in there!