Hi Lorraine, at my six week check I asked my doc if I could get back down the gym and she said not to unless it was low-impact on the treadmill. Pre-pregnancy, and up until I was 12weeks, I was doing yoga, Body Pump (high impact weights resistance training class thing) plus a visit to the gym and swimming weekly. When I got to 12weeks it was getting towards winter and I was so exhausted each evening I couldn't face going out and so knocked it all on the head but continued to have two fifteen minute walks every day until I was about 7/8 months. In all, about a week after having Emilia I was only 1stone over what I was before I was pregnant, however because I am not toned atall in the slightest anymore I am almost 2dress sizes bigger than I was and look much more than a stone! I breastfed for 5/6 weeks, so I don't think that was long enough to ascertain whether the weight loss was through breastfeeding or birth!
My diet is very similar to yours, I eat lots of fresh fruit and veg and very little "bad food" but I still haven't managed to shift that extra stone and I go out and walk at least once every day, and do all of the housework at the moment with as much gusto as possible.
As with your other question, I don't think I can give an answer but at least you are not alone. I am going to go see my GP next week some time so will mention it to her again as I seriously miss my fitness classes, and as much as I love my little bundle I could really do with an hour or so a week lifting something heavy that isn't her LOL!