Dont worry hun, it'll be fine!
At my 16 week appointment they checked urine, blood pressure, asked how I was feeling, then listened for Bubs HB. They did say that sometimes it's a little early to hear it, and I know of some girls that didin't even get the option of trying to find it as their midwives dont try so early - so you've got absolutely nothing to worry about.
As for weight, I got weighed at my booking appointment and my 12 week scan, and not since!
Good luck x
Crackers (21+5)