If you want to increase your carbs, do it. I'd just make sure they came from allowable veggies. I doubt you'll slow your weight loss that way, and you'll probably make it easier to get all your needed nutrients.

I think you're fine losing that quickly, unless there are other symptoms developing from it. I've lost the same amount, but in a bit over 4 months, so I say congrats and keep up the good work.