PANIC! 90th percentile and gestational weight

26 week growth scan today, baby is doing well but is measuring in the 90th percentile at 2lbs 4 (1010g). I am told to expect a big baby, possibly more than 9lbs. Is this dangerous?

Before I was pregnant I weighed between 65-70kg (I suffer with chronic illness so it does vary) and I am now weighing 79kg. All gestational weight calculators are telling me I’ve put on too much weight.

Honestly, I have been eating lots of carbs and sugar recently and am feeling terrible now. I have the glucose test next week, could I have caused gestational diabetes? I do lots of walking and am not sat down most of the day.

First time mum so maybe I’m overthinking but will these affect my ability to have a natural birth? I want as little medical intervention as possible and aim to breastfeed.