OP, I honestly thought I wouldn't gain more than a stone, I thought only women that had lots of junk food gained loads of weight, well I was wrong
I gained 3.5 stones by the end my pregnancy
I was so upset initially in the pregnancy when the weight started coming during my second trimester but then I made the decision that I was going to focus on eating well for my daughter and I would worry about the weight after.
So I was mindful, all my meals were made from scratch, I had fruit and vegetables with every meal, snacks were fruit, veg, protein
I did eat a lot, a lot more than I normally would, but I was so hungry and I was pregnant!!! Listen to your body.
After DD was born, I lost a stone immediately, then 6 weeks after the lochia had finished I'd lost another 9 pounds. Then after 9 months of breastfeeding and not particularly worrying about what I ate (I have been too busy trying to cope with the baby) I am finally back to my original weight.
Please do not worry. Eat well and be mindful. But don't beat yourself up, making and having a child is a big undertaking, after baby is born breastfeeding that child is bloody hard work too. You will find yourself again, but for now try to enjoy the weight, you're doing something amazing.